Pathoma and Key Word Associations Flashcards
(118 cards)
The testes of the gonadal male secrete?
Anti-mullerian hormone and testosterone
Testosterone aids in the development of what during male development?
Growth and differentiation of the Wolffian ducts which will develope into the internal male genital tract
What is the role of anti-mullerian hormone?
Causes atrophy of the mullerian ducts
What is the major androgen secreted by the Leydig cells?
Testosterone
How does LH act on the testes?
Stimulates Leydig cells to produce more testosterone by increasing cholesterol desmolase
The prostate and other accessory organs contain what enzyme for testosterone?
5 alpha-reductase, which will convert testosterone into more active dihydrotestosterone
Why are 5 alpha-reductase inhibitors (finasteride) used to treat BPH?
because they block the activation of testosterone to dihydrotestosterone in the prostate.
What is the main precursor of testosterone?
Cholesterol
How does FSH from the anterior pituitary act to regulate action of the testes?
FSH acts on sertoli cells to maintain spermatogenesis.
Sertoli cells secrete what that acts as a negative feedback inhibitor on the anterior pituitary?
Inhibin
How does LH from the anterior pituitary act to regulate action of the testes?
LH acts on Leydig cells to promote testosterone synthesis.
What is the negative feedback mechanism of testosterone on LH?
inhibiting the release of GnRH from the hypothalamus and by directly inhibiting the release of LH from the anterior pituitary.
What happens during puberty in regards to GnRH levels and what is the effect of this?
Puberty is initiated by pulsatile GnRH release from the hypothalamus. LH and FSH are secreted in a pulsatile fashion. GnRH also upregulates its own receptor in the anterior pituitary
Describe the synthesis of estrogen and progesterone in the female.
Theca cells produce testosterone which is stimulated by LH from the anterior pituatary. Androstenedione diffuses to nearby granulosa cells, which contain 17β-hydroxysteroid dehydrogenase, which converts androstenedione to testosterone, and aromatase, which converts testos- terone to 17β-estradiol (stimulated by FSH).
During the follicular phase of the menstrual cycle the hormone estrogen has what type of feedback?
Negative feedback on the anterior pituitary
During the midcycle phase of the menstrual cycle the hormone estrogen has what type of feedback?
Positive feedback on the anterior pituitary
During the luteal phase of the menstrual cycle the hormones estrogen and progesterone have what type of feedback?
Negative feedback on the anterior pituitary
What are the characteristics of the follicular phase?
Primordial follicle develops into the graffian stage with atresia of the neighboring follicles LH and FSH are up-regulated on theca and granulosa cells Estradiol levels increase and cause proliferation of the uterus FSH and LH levels are suppressed by the negative feed back effect of estradiol on the anterior pituitary.
What are the characteristics of ovulation (day 14)?
A burst of estradiol synthesis at the end of the follicular phase has positive feedback on the FSH and LH secretion (LH surge) Ovulation occurs as a result of the estrogen-induced LH-surge Cervical mucus increases in quantity, becoming less viscous and easily penetrated by sperm
What are the characteristics of the luteal phase?
Corpus luteum begins to develop and it synthesizes estrogen and progesterone Vascularity and secretory activity increase to prepare for receipt of a fertilized egg. Basal body temperature increases due to role of progesterone on the hypothalamus If there is no fertilization, the corpus luteum will regress and estradiol and progesterone levels will decrease abruptly
Abrupt withdrawal of estradiol and progesterone will cause what?
Menses, the endometrium is sloughed off
In pregnancy, the increasing levels of estradiol and progesterone will have what effect?
Maintenance of the endometrium for the fetus, suppress ovarian follicular function (by inhibiting FSH and LH secretion), and stimulate development of the breasts.
If there is proper fertilization, what is the role of hCG on the corpus luteum?
hCG produced by the placenta will rescue the corpus luteum from regression
What is the role of the corpus luteum during the first trimester?
It is responsible for the production of estradiol and progesterone

