Lecture 1 - Endocrine Overview

Question 1

Alpha-1, Alpha-2, and Beta adrenergic receptors are coupled to which G-proteins, respectively?

Answer 1

Alhpha-1 –> Gq

Alpha-2 –> Gi

Beta –> Gs

Question 2

Ach binds to ______ receptors in skeletal muscle, _____ receptors in Heart muscle (which are coupled to ____), and ____ in Salivary glands (which are coupled to _____).

Answer 2

Nicotinic

M2

Gi

M1

Gq

Question 3

Thyroid hormones are synthesized from _____ residues of protein precursors stored in a colloidal form in the thyroid gland.

Answer 3

Tyrosine

Question 4

Catecholamine half-life in blood is about ___-___ minutes, and response to catecholamines occurs in seconds or less.

Peptide hormones half-life in blood is about ___ minutes to several ____, and response to peptide hormones occurs in seconds to minutes.

Steroid/thyroid hormones half-life in blood ranges from about ____mins to hours or days. Response occurs in hours to days.

Answer 4

1-3mins

2mins to several hours

30mins

Question 5

T4 (Thyroxine) acts in a very similar way to _____ hormones. While their mech of action is controlling transcription and stability of mRNA, the mech of action for Peptide and Catecholamine hormones is activation of _____ messengers.

Which hormones are associated with protein kinase activation and which are associated with changes in membrane potential?

Answer 5

Steroid

Second messengers

Peptide hormones –> Protein Kinase activation

Catecholamines –> Changes in membrane potential