Flashcards in Pharm Quiz 5 - Werner TS Deck (84):
What are three things that cause uncontrolled proliferation in cancer cells?
intracellular signaling pathways
What 2 tumors is remission usually achieved?
malignant lymphoma and tvt
What type of drug forms covalent bonds with DNA and impedes replication?
What do protein kinase inhibitors do?
inhibition of tyrosine kinase that transduce growth signals in rapidly dividing cells
What are the 4 main problems associated with giving chemotherapy?
1. extravasation of drug
2. anaphylactic rxns
3. toxic side effects
4. acute tumor lysis syndrome
What can acute tumor lysis syndrome cause?
high uric acid, high P, high Ca, high K, acidosis --> depression, vomiting, hyperventilation
What can BCG (bacille calmetter guerin) be used for?
enhance tumor destruction, SCC
What are the SE of BCG?
local and systemic anaphylaxis
What is the MOA of cisplatin?
local denaturation of DNA
What are the SE of cisplatin?
nephrotoxic, low myelotoxicity, nausea
What is the MOA of methotrexate?
antimetabolite, folate antagonist
What are the SE of methotrexate?
bone marrow suppression, GIT irritation
What is the MOA of 5-flourouracil?
What is the MOA of alkylating agents?
formation of a carbonium ion --> intereferes with transcription and replication
What are the SE of alkylating agents?
BM, GI, sterility, cross resistance
What are the SE of cyclophosphamide?
alopecia, hemorrhagic cystitis
What alkylating agents are in the nitrogen mustard group?
cyclophosphamide, melphalan, chorambucil, ifosfamide
What is the slowest working alkylating agent and therefore lowest chance of toxicity?
What alkylating drug is a oral nitrosurea drug?
What kind of alkylating drug is dacarbazine?
What can cytotoxic antibiotics not be combined with to avoid toxicity?
What is the MOA of doxorubicin and the anthracyclines?
inhibits DNA and RNA synthesis
What is the MOA of dactinomycin?
intercalates in DNA interfering with RNA polymerase and with action of top II
What is the MOA of bleomycin?
fragmentation of DNA chains, non dividing cells
What is the MOA of L-asparaginase?
depletes intracellular stores of l asparagine --> no protein synthesis
What are the SE of L-asparaginase?
What is the MOA of the plant derivitave periwinkle chemotherapy drugs? (vincristine, vinblastine, vindesine)
bind to tubulin, inhibit polymerizaton to microtubules - arrest in metaphase
What are the SE of plant derivatives vincristine, vinblastine, vindesine?
mild BM, parasthesia, muscle weakness
What are the MOA of paclitaxel and docetaxel?
stabilize microtubules in polymerized state
How is paclitaxel and docetaxel given?
paclitaxel - IV
docetaxel - PO
What are teh SE of paclitaxel and docetaxel?
serious BM, cumulative neurotoxicity, dont use in horses
What tyrosine kinase inhibitor is used for mast cell tumors and sarcomas in dogs and cats?
What tyrosine kinase inhibitor is used for mast cell tumors in dogs only?
What antibody drug combats ErbB-1 expressing tumors?
What antibody drug combats ErbB-2 expressing tumors?
What antibody drug combats VEGFR in mastocytoma cells?
What can cause tumors to develop glucocorticoid resistance?
induction of PgP expression
What drugs are helpful in perianal gland tumors?
What drug is a selective inhibitor of estrogen receptors?
What drugs may be useful in some mammary tumors?
How can a tumor develop resistance against doxorubucin?
altered activity of the target
How can a tumor develop resistance against alkylating agents?
rapid repair of drug induced lesions
What does FSH stimulate in the female?
follicular growth, LH receptors, estrogen production
What does LH stimulate in the female?
estrogen production, rupture of follicle, progesterone by CL
What does FSH stimulate in male?
protein and nutrients for sertoli cells --> sperm
What does LH stimulate in male?
testosterone synthesis in leydig cells
What G protein receptor is GnRH?
What are the messengers involved in GnRh receptor signaling?
Gq -->Phospho C -->IP3 + DAG --> Ca + PKC --> MAP kinase --> gene expression
What is the synthetic GnRH preperation?
What kind of dosing is need for gonadorelin for infertility therapy?
intermittent dosing (mimicking physio)
What does continuous administration of gonadorelin do?
suppression of gonadotropin release - chemical castration/limit estrus
What are the 4 gonadotropins?
Lh, FSH, hCG, eCG
What do all the gonadotropins have in common with their structure?
glycosylated heterodimers with alpha and beta subunits
Which 2 gonadotropins have 82% homology?
LH and hCG
Which subunit of the gonadotropins confers specificity?
the beta subunit (where and how strong it will bind)
What feedback effect do steroid hormones have on the pituatary and hypothalamus?
What kind of receptors are FSH and LH?
g-coupled --> adenylate cyclase -> increase cAMP (different than GnRH which is Gq)
What is human chorionic gonadotropin (hCG) used for clinically? why?
induce ovulation in mares with appropriate follicle size
similar to equine LH
What is the difference between hCG and LH?
hCG lasts alot longer (is a glycoprotein)
What produces equine chorionic gonadotropin (eCG)?
endometrial cups to induce secondary corpora lutea
What are the 2 effects of eCG?
primarily FSH --> increase follicular growth
LH activity --> ovulation and luteinization
What is the clinical use of eCG?
ovarian follicle growth in anestrus sheep or goats, induction of estrus in pigs
What are the adverse effects of eCG?
immunological rxns to antibody formation, loss of efficacy
What molecule is oxytocin very similar to?
What transports oxytocin from the hypothalamus to pituatary?
oxytocin-neurophysin 1 complex
What is the natural prostaglandin produced by endometrium of farm animals?
What is the MOA of PGF 2 alpha?
Gq coupled - IP3 - Ca - protein kinase C (similar to GnRH
What are the 2 effects of PGF 2 alpha?
steroidgenesis and luteolysis
What are the adverse effects of prostaglandin analogs?
contracts smooth muscle - GI, etc
What are the 3 clinical uses of prostaglandin analogs?
abortion and partruition
uterine contractions in mares for mating induced endometritis
What protein transports estrogens?
sex hormone binding globulin (SHBG)
What estrogen has low oral bioavailability because of the first pass effect?
What are the effects of estrogens?
modify protein levels, reduce bone resorption, negative feedback on LH and FSH
What are the adverse effects of using estrogens?
breast cancer (humans), endometrial hyperplasia, uterine carcinoma
Why must synthetic progesterone analogs be used?
rapidly metabolized in liver, short half life of regular progesterone
What is the clinical use of progesterone?
induce long lasting ovarian suppression and estrus synchronization (bad behavior in mares)
What is the MOA of progesterone analogs?
acts on receptors in hypo and pitua, suppress LH and FSH
What receptors do anabolic steroids have an effect?
nuclear receptors - ligand gated transcription factors
What is the alkylated anabolic steroid used?
What is the non alkylated anabolic steroid?
What are the adverse effects of anabolic steroids?
weight gain, hepatotoxic, carcinogenicity
What are some drugs that can not be used in food producing animals?
antibiotics, diethylstilbesterol, clenbuterol, dipyrone, antiviral drugs (adamanane, neuraminidase inhibitors)
What are approved drugs for extralabel used in food animals?
enrofloxacin, sulfonamides, medicated feeds