Pathology of Endocrine System Flashcards
1
Q
What is the function of the endocrine system?
A
to secrete product (hormone) into the blood stream
2
Q
Generally, what is secretion in the endocrine system controlled by?
A
feedback mechanisms
3
Q
What hormone types are excreted by the endocrine system?
A
protein and peptides, amino acid derivatives, and steroid and fatty acid derivatives
4
Q
What do protein and peptide derivatives bind to?
A
target cell surface receptors
5
Q
What parts of the endocrine system secrete protein and peptide hormones?
A
pituitary, parathyroid, C-cells, and islets of Langerhans
6
Q
What parts of the endocrine system secrete amino acid derivatives?
A
adrenal medulla and thyroid
7
Q
What do steroid and fatty acid derivative hormones bind to?
A
target cell cytoplasmic receptors
8
Q
What part of the endocrine system secretes steroid and fatty acid derivative hormones?
A
adrenal cortex
9
Q
What are some productive lesions of the endocrine organs?
A
hyperplasia and neoplasia
10
Q
What are some destructive lesions of the endocrine organs?
A
hypoplasia, atrophy, inflammation, necrosis, amyloidosis, surgical misadventure, and neoplasia
11
Q
When is hyperplasia of endocrine organs functional?
A
increased trophic stimulus
12
Q
When is hyperplasia of endocrine organs nonfunctional?
A
aging
13
Q
What is atrophy of endocrine organs caused by?
A
decrease in trophic stimulus, inflammation, and necrosis
14
Q
Clinically significant endocrine disease is due to what?
A
an increase or a decrease in hormone function
15
Q
What are the types of hyperfunction?
A
primary or secondary hyperfunction
16
Q
What is primary hyperfunction?
A
uncontrolled increase in hormone production
17
Q
What is secondary hyperfunction?
A
increase in hormone production due to increase in trophic stimulus
18
Q
Hyperfunction causes what?
A
decreased breakdown, production of hormone-like molecules, and lactogenic/exogenous intake
19
Q
What are the types of hypofunction?
A
primary and secondary
20
Q
What is primary hypofunction?
A
decrease in hormone production due to destriction of a gland
21
Q
What is secondary hypofunction?
A
decreased hormone production due to decrease in trophic stimulus
22
Q
What are some lesions of endocrine diseases in non-endocrine tissues?
A
epidermal atrophy, bilaterally symmetrical alopecia, hepatic lipidosis, soft tissue mineralization, artherosclerosis, muscle atrophy, cataract, and PU/PD
23
Q
What is the adenohypophysis?
A
the anterior pituitary
24
Q
What is the adenohypophysis derived from?
A
oral ectoderm (Rathke’s pouch)
25
What are the parts of the adenohypophysis?
pars distalis, pars intermedia, amd pars tuberalis
26
What does the pars distalis produce?
acidophils, basophils, and chromophobes
27
What hormones are the acidophils?
GH, prolactin, ACTH
28
What hormones are the basophils?
FSH, LH, TSH
29
What hormones are chromophobes?
pro-opiomelanocortin which is cleaved into ACTH, MSH, and beta-endorphin)
30
What is the pars distalis stimulated by?
releasing factors from the hypothalamus
31
What is the pars distalis down regulated by?
increase in blood hormone from the target gland
32
Where is the pars intermedia located?
adjacent to the pars nervosa
33
What does the pars intermedia secrete?
chromophobes (POMC)
34
What is chromophobe secretion from the pars intermedia down regulated by?
an increase in dopamine
35
What does the pars tuberalis surround?
the hypophyseal stalk
36
What is the neurohypophysis?
the posterior pituitary
37
What is the neurohypophysis derived from?
the neuroectoderm
38
What is the pars nervosa?
part of the neurohypophysis that contains axons from neurons in hypothalamic nuclei
39
What nuclei are in the pars nervosa?
supraoptic nucleus and paraventricular nucleus
40
What does the supraoptic nucleus produce?
ADH
41
What does the paraventricular nucleus produce?
oxytocin
42
What lesions are associated with the pituitary gland?
aplasia, hypoplasia, abscess, neoplasms of adenohypophysis
43
What are neoplasms of the adenohypophysis usually?
chromophobe; adenoma or carcinoma
44
Are neoplasms of the adenohyophysis functional or nonfunctional?
they can be both
45
What hormones are associated with functional neoplasms of the adenohyophysis?
ACTH and GH
46
What does increased ACTH due to a functional neoplasm of the adenohypophysis cause?
adrenal cortical hyperplasia which causes hypercortisolism
47
What does increased GH due to a functional neoplasm of the adenohyophysis cause?
gigantism, acromegaly, and refractory DM in cats
48
What generally do expansion neoplasms of the adenohypophysis cause?
compresses/destroys adjacent parenchyma
49
What hormones are associated with expansion neoplasms in adenohypophysis?
ADH and TSH
50
What does decreased ADH cause?
diabetes insipidus
51
What deos decreased TSH cause?
thyroid atrophy which leads to hypothyroidism
52
What clinical syndromes are associated with the pituitary gland?
juvenile panhypopituitarism, equine chromophobe adenoma of Pars Intermedia/Pituitary Pars intermedia dysfunction, and canine chromophobe adenoma
53
What species does juvenile panhypopituitarism typically affect?
dogs - german shepards
54
What hormone changes are associated with panhypopituitarism?
decreased GH, ACTH, TSH, FSH, and LH
55
What lesions are associated with juvenile panhypopituitarism?
stunted, retained puppy hair coat
56
What hormone changes are associated with equine chromophobe adenoma of pars intermedia/pituitary pars intermedia dysfunction?
+/- increase in ACTH and or increase of POMC
57
When equine chromophobe adeonma of pars intermedia/pituitary pars intermedia dysfunction expands into the hypothalamus, what happens?
there is impaired ADH production
58
What lesions are associated with equine chromophobe adenoma of pars intermedia/pituitary pars intermedia dysfunction?
hirsutism, +/- adrenal cortical hyperplasia, hyperhidrosis, lethargy, and PU/PD
59
What type of neoplasm is canine chromophobe adenoma?
a functional one
60
What does canine chromophobe adenoma cause?
an increase in ACTH causing diffuse adrenal cortical hyperplasia
61
Canine chromophobe adenoma causes pituitary - ______ ________.
dependent hyperadrenocorticism
62
What is the structure of the thyroid gland?
bilobed or 2 glands
63
What are the follicles of the thyroid gland composed of and what do they produce?
follicular cells - colloid
64
What does iodinated colloid cause?
T3 and T4 (thyroxine)
65
What is the thyroid controlled by?
a feedback loop
66
What is the feedback loop of the thyroid gland?
decrease in T3/T4 to increased TSHrf and increased TSH to follicular hyperplasia and colloid production to increased T3 and T4
67
What is the thyroid composed of?
capsule, follicular cells, and C-cells
68
What is the capsule of the thyroid composed of?
reticular connective tissue
69
What are follicular cells composed of?
single layer cuboidal secetory epithelium and eosinophilic cytoplasm
70
What are C-cells?
parafollicular cells
71
Where are c-cells located?
they are polygonal cells between follicles
72
What do c-cells secrete?
calcitonin
73
What is the function of calcitonin?
it decreases serum calcium
74
What lesions are associated with the thyroid gland?
atrophy, enlargement due to hyperplasia, adenomatous hyperplasia, nodular gitre, neoplasms, and lymphocytic thyroiditis
75
What is enlargement due to hyperplasia also called?
goiter
76
What is goiter caused by?
iodine deficiency due to goitrogenic plants and chemicals
77
What species does adenomatous hyperplasia effect?
old cats
78
What does adenomatous hyperplasia of the thyroid cause?
hyperthyroidism
79
What neoplasms are associated with the thyroid gland?
adenoma or carcinoma
80
What type of disease is lymphocytic thyroiditis?
an autoimmune disease
81
What does lymphocytic thyroiditis result in?
atrophy which causes hypothyroidism
82
What clinical syndromes are associated with the thyroid gland?
hypothyroidism and hyperthyroidism
83
What does dogs are lazy and cats are crazy refer to?
dogs get hypothyroidism (weight gain) and cats get hyperthyroidism (weight loss)
84
What does hypothyroidism cause in the thyroid?
atrophy
85
What clinical signs are associated with hypothyroidism?
BS alopecia, epidermal atrophy, myxedema, obesity, lethargy, arthersclerosis, and hypercholesterolemia
86
What other animals does hypothyroidism affect?
horses, sheep, and goats
87
What does hypothyroidism in horses, sheep, and goats cause?
hyperplastic goitre
88
What clinical signs are associated with hypothyroidism in horses, sheep, and goats?
mandibular prognathism, BS alopecia, epidermal atrophy, and myxedema
89
What does hyperthyroidism cause in cats?
adenomatous hyperplasia
90
What clinical signs does hyperthyroidism cause in cats?
hyperactivits, hunger, tachycardia, hypertrophic CM
91
What is hyperthyroidism known as in humans?
Grave's disease
92
What happens in Grave's disease?
TSH receptor antibody which mimics TSH which causes hyperplasia
93
What lesions are associateed with C-cells?
atrophy, hyperplasia, and neoplasia
94
What does atrophy of C-cells happen in response to?
persistent hypocalcemia
95
What does hyperplasia of C-cells happen in response to?
persistent hypercalcemia
96
What neoplasm is associated with c-cells?
thyroid medulalry carcinoma
97
Where are the adrenal glands located?
retroperitoneally, adjacent to the kidneys
98
What are the regions of the adrenal gland?
cortex and medulla
99
What is the capsule of the adrenal gland made up of?
reticular connective tissue
100
What is the capsule of the adrenal gland adjacent to?
autonomic ganglia
101
What is the cortex of the adrenal gland derived from?
cholesterol - mesoderm
102
What are hormones are associated with the cortex of the adrenal glands?
mineral corticoids, glucocorticoids, and androgens
103
What is the medulla of the adrenal glands derived from?
catecholamines - neural crest
104
What hormones are associated with the medulla of the adrenal glands?
epinephrine and norepinephrine
105
What are the layers of the adrenal cortex?
zona glomerulosa, zona fasiculata, and zona reticularis
106
Which layer of the adrenal cortex is the superficial layer?
zona glomerulosa
107
What is the histological structure of the zona glomerulosa?
columnar cells aligned in arching cords
108
What does the zona glomerulosa do?
it produces aldosterone in response to angiotensin II which increases Na resorption and increases potassium excretion
109
What layer of the adrenal cortex is the middle layer?
zona fasiculata
110
What is the histological structure of the zona fasiculata?
columnar to polygonal cells with small vacuoles
111
What is the function of zona fasiculata?
produces cortisol in the response to ACTH
112
What layer of the adrenal cortex is the inner layer?
zona reticularis
113
What is the histologial structure of zona reticularis?
polygonal cells with small vacuoles
114
What does zona reticularis do?
produces androgens (and estrogens in some animals)
115
What regulates the adrenal medulla?
the sympathetic nervous system
116
What does the adrenal medulla release?
epinephrine and norepinephrine from preformed granules
117
What cell types make up the adrenal medulla?
chromaffin cells and ganglion cells
118
What is the structure of chromaffin cells in the adrenal medulla?
aligned in cords and clusters on fibrovascular stroma and sinusoids
119
What do chromaffin cells contain?
epinephrine and norepinephrine in preformed granules
120
What is the function of ganglion cells in the adrenal medulla?
they receive sympathetic stimuli and cause chromaffin cells to degranulate
121
What lesions are associated with the adrenal cortex?
diffuse atrophy, hyperplasia, adrenalitis, hemorrhage, necrosis, and neoplasms
122
What is diffuse atrophy of the adrenal glands caused by?
decreased ACTH, glucocorticoids, OPDDD, secondary to Lc adrenalitis
123
What is nodular adrenal cortex hyperplasia caused by?
incidental aging change
124
What is diffuse adrenal cortex hyperplasia caused by?
increased ACTH or idiopathic
125
What are the types of adrenalitis?
lymphocytic and granulomatous
126
What is lymphocytic adrenalitis caused by?
autoimmune disease
127
What is granulomatous adrenalitis caused by?
fungal or mycobacterial infection
128
What is adrenal cortex hemmorhage caused by?
gram negative sepsis
129
How does adrenal cortex necorosis present?
diffuse with hemorrhage
130
What is multifocal adrenal cortex necrosis caused by?
neonatal herpesvirus infections
131
What neoplasms are associated with the adrenal cortex?
adenoma and carcinoma
132
What lesions are associated with the adrenal medulla?
neoplasms - pheochromocytoma
133
What clinical syndromes are associated with the adrenal glands?
canine hyperadrenocorticism, hyperadrenocorticism, and hypoadrenocorticism
134
What is canine hyperadrenocorticism also known as?
Cushing's like disease
135
What causes canine hyperadrenocorticism?
increased cortisol or exogenous glucocorticoid
136
What are different scenarios/types of canine hyperadrenocorticism?
functional chromophobe tumor, functional adrenal coertical tumor, idiopathicadrenal cortical hyperplasia, and lactogenic glucocorticoid excess
137
What does functional chromophobe tummor in canine hyperadrenocorticism cause?
an increase in ACTH leading to diffuse adrenal cortical hyperplasia
138
What does a functional adrenal cortical tumor in canine hyperadrenocorticism lead to?
increased cortisol causing a tumor plus diffuse adrenal cortical atrophy
139
How does idiopathic adrenal cortical hyperplasia present?
diffuse adrenal cortical hyperplasia
140
How does lactogenic glucocorticoid excess present?
diffuse adrenal cortical atrophy
141
What lesions and clinical signs are associated with canine hyperadrenocorticism?
BS alopecia, epidermal atrophy, calcinosis cutis, pot belly, muscle atrophy, hepatomegaly with vacuolar degeneration, and PU/PD
142
How does hyperadrenocorticism present in ferrets?
diffuse or nodular cortical hyperplasia; cortical adenoma
143
What hormone changes are associated with hyperadrenocorticism in ferrets?
increased estrogen production
144
What lesions and clinical signs are associated with hyperadrenocorticism in ferrets?
BS alopecia, epidermal atrophy, feminization, persisten estrus, and pancytopenia leading to hemorrhage
145
What is another name for hypoadrenocorticism?
Addison's like disease
146
What is Addison's like disease most common in?
dogs - rottweilers
147
What lesions are associated with Addison's like disease?
diffuse adrenal cortical atrophy leading to decreased mineralo and glucocorticoids
148
What is Addison's like disease secondary to?
adrenalitis or therapy
149
What clinical signs are associated with Addison's like disease?
collapse, dehydration, bradycardia, hyperkalemia and hyponatremia
150
What are the islets of langerhans?
multicell clusters scattered throughout the pancreas
151
What is the histologic presentation of islets of langerhans?
cuboidal to columnar cells; pale cytoplasm
152
What cell types make up the Islets of Langerhans?
alpha cells, beta cells, gamma cells, G cells and PP cells
153
What do alpha cells secrete?
glucagon which increases blood glucose
154
What do beta cells secrete?
insulin to decrease blood glucose and IAPP which slows gastric emptying and promotes satiety
155
What do gamma cells secrete?
somatostatin which is an antagonist to GH
156
What do G cells secrete?
gastrin which increases HCL secretion in the stomach
157
What do PP cells secrete?
pancreatic polypeptide
158
What lesions are associated with Islets of Langerhans?
atrophy/loss, vacuolation, lymphocytic isleitis, neoplasms
159
What is atrophy/loss of Islets of Langerhans?
loss of islets due to inflammation
160
What is vacuolation of the Islets of Langerhans associated with?
diabetes
161
What is lymphocytic isletitis associated with?
inflammation
162
What species is islet amyloidosis seen in?
cats and primates
163
What neoplasms are associated with Islets of Langerhans?
adenoma and carcinoma
164
What are the differenttypes of diabetes mellitus?
type I and type II
165
What causes type I diabetes mellitus?
overt insuline deficiency
166
What species does type I diabetes mellitus manifest in?
dogs
167
What occurs to the pancreas in type I diabetes mellitus?
autoimmune isletitis and chornic pancreatitis
168
What causes type II diabetes mellitus?
insulin antagonism with or without impaired secretion
169
What species does type II diabetes mellitus typically manifest in?
cats and humans
170
What is type II diabetes mellitus antagonized by?
cortisol, glucagon, GH, estrogen, IAPP, and obesity
171
What occurs to the pancreas in type II diabetes mellitus?
ultimate islet exhaustion
172
What lesions/clinical signs are associated with diabetes mellitus?
hepatic lipidosis, islet vacuolation, cataracts, +/- weight loss, golmerulosclerosis, microangiopathy, islet amyloidosis, persistent hyperglycemia, glucosuria, PU/PD, polyphagia
173
What species do islet cell neoplasms typically occur in?
dogs and ferrets
174
What are the types of islet cell neoplasms?
islet cell adenoma, islet cell carcinoma, insulinoma, and gastrinoma
175
Where do islet cell carcinomas typically metastasize to?
the liver
176
What do insulinomas cause?
increased insulin secretion leading to hypoglycemia
177
What do gastrinomas cause?
increased gastrin secretion leading to hyperacidity causing a gastric ulcer
178
What is the structure of the parathyroid glands?
4 small spherical glands associated with thyroid glands in dogs and cats
179
What cells are part of parathyroid glands?
chief cells
180
What do chief cells secrete and what is it regulated by?
parathormone which is regulated by serum ionized calcium
181
What does parathyroid hormone maintain?
minute to minute control of serum ionized calcium by affecting bone resporption and increased Ca resorption and increased P excretion in the kidney
182
Parathyroid hormone works in concer with what other nutrient?
vitamin D
183
What lesions are associated with parathyroid glands?
hypertrophy and hyperplasia, atrophy, lymphocytic parathyroiditis, and neoplasia
184
What does hypertrophy and hyperplasia of the parathyroid glands cuase?
enlarged glands due to an increased number of chief cells
185
What does hypertrophy and hyperplasia of the parathyroid respond to?
chronic hypocalcemia by increasing prodction of PTH
186
What does atrophy of the parathyroid gland respond to?
chronic hypercalcemia or chronic inflammation
187
Neoplasms of the parathyroid glands are typically _______ and frequently _____.
benign; functional
188
What clinical syndromes are associated with the parathyroid glands?
hyperparathyroidism, pseudohyperparathyroidism, and hypoparathyroidism
189
What do both types of hyperparathyroidism result in?
fibrous osteodystrophy
190
What chemical changes are associated with primary hyperparathyroidism?
functional PTH adenoma causing increased PTH leading to hypercalcemia and fibrous osteodystrophy
191
What renal chemical changes are associeated with secondary hyperparathyroidism?
chronic renal failure leading to increased P, decreased Ca and D3 causing a chronic Ca drain
192
What nutritional changes are associated with secondary hyperparathyroidism?
decreased dietary calium and vitamin D or increased dietary phosphorus
193
What does pseudohyperparathyroidism cause?
production of a PTH-like molecule
194
What lesions are associated with pseudohyperparathyroidism?
anal sac adenocarcinoma in dogs and lymphosarcoma
195
What are the causes of hypoparathyroidism?
lymphocytic parathyroiditis, inadvertent surgical removal of the PTH glands, and periparturient hypocalcemia
196
What causes periparturient hypocalcemia?
decreased serum Ca due to fecal mineralization or lactational demand
197
What is a specific syndrome associated with hypoparathyroidism in dogs and mares?
eclampsia
198
What does eclampsia cause?
hyperexcitability and tetany
199
What is an example of hypoparathyroidism in cows?
milk fever
200
What does milk fever cause?
paresis leading to paralysis due to decreased Ach release at the neuromuscular junction
201
What are some additional causative factors of milk fever?
high prepartum dietary Ca, inappatence at parturition, alkalosis causes inhibition of PTH receptors
