Page 82 - Physiology and Pathophysiology MNU 2024-2025 نظرى

Clinical pharmacy 2024/2025 Level 2 Pharm D Physiology and Pathophysiology (MD303)
Antidiuretic hormone secretion is regulated by several factors:

Plasma osmolarity Blood volume & Blood pressure alcohol
The primary factor that   blood volume of 10% or more Inhibits the

influences ADH secretion. OR in mean arterial blood secretion of ADH
 plasma osmolarity  pressure of 5% or more    loss of water
Stimulation of ADH secretion  from the kidney.

osmoreceptors in vasoconstriction & antidiuresis  Therefore,
hypothalamus   blood volume & blood pressure consumption of
stimulation of the back to normal. alcoholic
neurosecretory cells  During sleep  blood pressure beverages  

release of ADH  water decreases   ADH secretion  water loss.
conservation   plasma production of a low volume of highly
osmolarity or dilute the concentrated urine  less likely to

plasma back to normal. elicit the micturition (urination)
reflex & interrupt sleep
Abnormalities Uses

Deficiency: diabetes insipidus a. Treatment of diabetes insipidus.
Excess: Inappropriate water b. As a vasoconstrictor with local anesthetics.

retention c. In adults with persistent enuresis.

2- Oxytocin

1- Stimulates contraction of the smooth muscle in the wall of the

uterus.
a. During labor  facilitates the delivery of the fetus.
b. During intercourse  facilitate the transport of the sperm through
Action the female reproductive tract.

2- contraction of the myoepithelial cells surrounding the alveoli of the
mammary glands  milk letdown

The secretion of oxytocin is regulated by reflexes elicited by cervical
stretch and by suckling

few symptoms, as it is only required at the time of childbirth &
Deficiency
breastfeeding
Excess no clinical condition.

Uses a. To induce or augment labor when the uterine muscle is not
functioning adequately.

| P a g e 58