Endocrine Flashcards
1
Q
Pancreatic alpha cells secrete —-
A
glucogon
2
Q
Pancreatic beta cells secrete —– and —–
A
Insulin and amylin
3
Q
Pancreatic delta cells secrete ——
A
somatostatin
4
Q
Pancreatic PP cells secete
A
pancreatic polypeptide
5
Q
T1/2 of endogenous insulin
A
6 minutes
6
Q
How is insulin degraded in the body
A
insulinase in the liver
7
Q
Insulin increases expression of —–
A
GLUT-4 (also AA transport, ion transporters)
8
Q
Insulin effects on the liver (4)
A
inactivation of phosphorylase –> halt breakdown of glycogen
Increase glycogen synthesis via activation of glucokinase
Inhibits gluconeogenesis
promote conversion of glucose to fatty acids
9
Q
Effect of insulin on fat
A
inhibit hormone-sensitive lipase
10
Q
Mechanism of glucose sensing in beta cells
A
Glucose enters cell –> ATP produced –> ATP inhibits ATP-sensitive K+ channel –> depolarization –> open voltage-gated Ca+2 channel –> Ca+2 facilitates exocytosis of insulin vesicles
11
Q
Hormones that lead to insulin release (2)
A
GLP-1 and GIP
12
Q
Glucagon effects on liver
A
activates gluconeogenesis and glycogenolysis
13
Q
Glucogon effect on fat
A
inhibits storage
activates lipolysis
14
Q
glucagon cardiovascular effects
A
increased contractility and blood flow
15
Q
exercise (increase/decrease) glucagon
A
increase
16
Q
increased blood amino acid (increase/decrease) glucagon
A
increase
17
Q
What triggers somatostatin release
A
food ingestion
18
Q
The action of somatostatin (4)
A
Decrease insulin secretion
Decrease glucagon secretion
decrease GI motility
decreases GI secretion and absorption
19
Q
Dogs get what kind of diabetes
A
Insulin dependant (type 1)
20
Q
Cats get what kind of diabetes
A
Insulin independent (type 2)
21
Q
Goal of glycemic control diabetes
A
BG 90-250
Nadir 90-150
22
Q
Causes of insulin resistance (4)
A
Obesity
inflammation
hormone excess/deficiency
hyperlipidemia
23
Q
Counterregulatory hormones (4)
A
glucagon, epinephrine, cortisol, and growth hormone
24
Q
Bexaglofozine and velaglifozin MOA
A
SGL-2 inhibitor
25
Exenatide MOA
GLP-1 agonist (simulates insulin, inhibits glucagon)
26
Glipizide MOA
Sulfourea K+ ATP channel inhibitor - stimulates insulin release
27
Acarbose MOA
alpha-glucosidase inhibitor, slows metabolism of carbohydrates
28
If diabetic remission will happen in a cat what is the usual time frame
3 mo - 1 yr
29
Diabetic diet dog
high fiber low fat
30
diabetic diet cat
low carb high protien
31
DKA definition
hyperglycemia, elevated ketones, acidosis, low bicarb
32
HHS definition
BG >600, OSM >325, no ketoacidosis
33
What do C cells of the thyroid produce
Calcitonin
34
How is iodine uptaken by thyroid
Na/I symporter
35
How is Iodine transported into the thyroid follicle
Pendrin (I/ Cl counter transporter)
36
Which is more potent T3 or T 4
T3
37
Which has a longer t1/2 T 3 or T4
T4
38
TSH increases T4 production via ---
cAMP
39
factors that increase TSH (2)
cold
anxiety
40
MOA methimazole
thyroperoxidase inhibitor
(oxidizes iodide and catalyzes coupling)
41
What happens when there is very high dietary iodide intake
T3/T4 production is supressed
42
Hyperthyroid cats ---% bilateral ---% unilateral ---% ectopic
70% bilateral, 25% unilateral 5 % ectopic
43
Gold standard hyperthyroid dx?
RIA TT4
44
screening test for feline hyperthyroid
TT4
45
reasons for false negative feline hyperthyroid (2)
mild/early disease
NTI
46
feline hyperthyroid test with higher sensitivity than TT4
FT4 (less specific though)
47
Expected TSH for cat with hyperthyroidism
0 (high sensitivity, low specificity fo hyperT4)
48
Expected results for TRH stimulation test in euthyroid and hyperthyroid cat
euthyroid >60% increase in TT4
hyperthyroid <50% increase in TT4
49
Scintigraphy results in euthyroid cat
1:1 uptake salivary to thyroid
50
Time expected to see a change in hormone level after starting methimazole
2-4 weeks
51
non-life-threatening AE methimazole and how to address (4)
GI upset -change dose/form
lethargy - change dose /form
facial excoriation - stop drug
leukopenia, eosinophilia, lymphocytosis - monitor CBC stop if worsening
52
Life-threatening AE methimazole (3)
hepatopathy
blood dyscrasia
Bleeding
53
what to do if cat is hypothyroid on methimazole
decrease dose 25-50%
54
How soon for normal T4 on a strict low I diet
6-8 weeks
55
AE of thyroidectomy cat (3)
hypocalcemia
horners
laryngeal paralysis
56
Causes of central hypothyroidism (3)
neoplasia
hypophysectomy
head trauma
57
causes of congenital hypothyrodisim (4)
pituitary dwarfism
TPO deficiency
Iodide deficiency or excess in dam
Thyroid hypoplasia/agenesis
58
Causes of primary hypothyroidism (2)
Lymphocytic thyroiditis
idiopathic atrophy
59
optho sign hypothyroidism
arcus lipoides
60
repro signs hypothyroidism (3)
low fertility
increase periparturient mortality
low birth weight
61
CBC changes associated with hypothyroidism (3)
NNN anemia
thrombocytosis
small platlets
62
chemistry changes associated with hypothyroidism (3)
hypercholesterolemia
hypertriglyceridemia
increased ALP/GGT
63
Screening test hypothyroidism
TT4
64
Reason for false negative hypothyroidism
T4AA
65
more specific test hypothyroidism than TT4
FT4
66
expected TSH in hypothyroid dog
high
67
significance of positive tgAA
supports a diagnosis of hypothyroidism
68
Breed with naturally lower T3/T4
sighthounds
69
Drugs that can interfere with thyroid testing (7)
-NSAIDS
-Steroids
-KBr
-phenobarbital
-sulfa drugs
- propanolol
- palladia
70
GI absorption of thyroxine
poor
71
AE thyroxine (2)
hypert4
skin reaction
72
when to monitor T4 after starting therapy
4 weeks, 4-6 hours post-pill
73
rate-limiting step of steroid hormone synthesis
Cholesterol --> pregnenolone by cholesterol desmolase
74
cortisol t1/2
60-90 min
75
aldosterone t1/2
20 min
76
Metabolism of steroid hormones
hepatic, conjugated with glucuronic acid and excreted in feces (+ renal)
77
cortisol is inactivated at mineralocorticoid receptor
functional but inactivated by 11beta - HSD2
78
aldosterone acts at what cell
principal cell in collecting duct
79
excess aldosterone causes (alkalosis /acidosis)
Alkalosis
80
Why is there minimal change in Na with aldosterone excess
pressure natriuresis
81
Major stimulators for aldosterone (2)
Ang II and K+
82
inhibitors of aldosterone (2)
hypernatremia, ANP
83
glucocorticoids decrease what cytokines
IL1, IL 8, TNF alpha
84
Pathophysiology Addisons
Lymphoplasmacytic adrenalitis CD4+ T cell infiltration
85
expected UCCR in Addison's
low
86
lymphocyte count associated with Addison's with 85% sensitivity
>2,000
87
----% canine (and feline) HAC patents have PDH
85%
88
Gold standard and expected results for iatrogenic Cushings
ACTH stim flatline response
89
escape pattern LDDST suggests
PDH
90
Flatline high LDDST suggest
PDH or AT
91
Trilostane MOA
competitively inhibits 3-beta-hydroxysteroid dehydrogenase
92
Time after starting trilostane clinical signs improve after starting trilostane
weeks
93
AE trilostane (3)
>10% fail to respond
Addison's
adrenal necrosis
94
Mitotane MOA
aderncoticolytic
95
AE mitotane (4)
addisons
neurotoxicity
hepatotoxicity
GI
96
Factors associated with acromegaly (2)
organohalogenated contaminants, AIP mutation
97
Streptozocin AE (3)
DM
nephrotoxicity
GI
98
Diazoxide MOA
Prevent insulin release via opening ATP-sensitive potassium channel (KATP) on the membrane of pancreatic beta‐cells, diazoxide promotes potassium efflux from beta-cells. This hyperpolarizes the cell membrane
99
name of syndrome associated with gastrinoma (and what it is)
Zollinger Ellison syndrome
-antral hypertrophy, hyperacidity, ulceration
100
provocative testing for gastrinoma includes giving -- or --
calcium or secretin
101
paraneoplastic syndrome associated with glucocomona
necrolytic migratory erythema
102
--% of body calcium is in theECF
0.1%
103
ECF calcium --% protein bound, ---% ionized, ---% complexed with anions
40% protein bound, 50 % ionized, 10 % complexed with anions
104
Hypocalcemia effects (3)
nervous system excitment (tetany), cardiac dilation, clotting disorder
105
Hypercalcemia EKG change
short QT interval
106
Most calcium in kidney is reabsorbed where
PCT
107
The enzyme that prevents hydroxyapatite deposition in soft tissue
pyrophosphotases
108
Osteoclast secrete --- to inhibit pyrophosphatase
TNAP
109
PTH causes the expression of ---- to cause osteoclast differentiation
RANKL
110
--- Opposes RANKL
OPG Osteoprotegerin
111
Glucocorticoids --- RANKL and -- OPG
increase
decrease
112
estrogen --- OPG
increases
113
Active form of vitamin D
1,25-dihydroxy vitamin D (cholecalciferol,)
114
Where is 25-hydroxyvitamin D synthesized
Liver
115
Where is 25-hydroxyvitamin Dconverted to 1,25-dihydroxy vitamin D
kidney
116
vitamin D actions (4)
increase Ca absorbtion in GIT via calbindin
increase phosphorus absorption in GIT
Decrease Ca and P excretion in the kidney
Alter bon resolution and formation (depends on dose)
117
What cells in the parathyroid secrete PTH
Chief
118
PTH exerts its effects via what second messenger
cAMP
119
How is ECF Ca sensed by parathyroid
Calcium sensing receptor sense Ca --> G protein receptor --> increases phospholipase C --> decrease PTH
120
action of Calcitonin
decrease blood Ca ( inhibiting osteoclasts and promoting calcium excretion in the kidneys.)
121
DX
High PTH
High vit D
high iCal
primary hyper parathyroid
122
DX
high PTH
Low vit D
high i cal
CKD (renal secondary hyperparathyroidism)
Ical can also be low :(
123
DX
low pth
high vit D
high i Cal
vit D tox
124
DX
low PTH
low vit D
low ical
hypotharathyroid
125
expected phosphate with hyperpartathyroidism
low
126
expected phosphate with renal disease
high
