VPB 121: Veterinary Physiology - II (2+1)

Functions of sympathetic and parasympathetic divisions

FUNCTIONS OF SYMPATHETIC AND PRASYMPATHETIC DIVISIONS

HETIC AND NS

Effector organ	Sympathetic	Receptor	Parasympathetic
Heart S A node	Increased in heart rate	b1	Decrease in heart rate
Atria	Increase contractility and conduction velocity	b1	¯ contractility & ­ conduction velocity
AV node and Conduction system	­ conduction velocity	b1	¯ conduction velocity
Ventricles	contractility & conduction velocity	b2	---
Arterioles Coronary, skeletal, Pulmonary, renal, Abdominal & skin	Vasoconstriction Dilatation	a b2	Dilatation
Systemic veins	Constriction or Dilatation	a / b2	---
Respiratory tract Bronchial muscles	Relaxation	b2	Contraction
Bronchial glands	Inhibition?		Stimulation
Smooth muscles G. I. Tract	Decreased motility Sphincter constriction Inhibits secretion?	a, b2 a	Increased motility Sphincter relaxation Stimulates secretion
Gall Bladder	Relaxation		Contraction
Urinary bladder Muscle Sphincter	Relaxation Contraction	b a	Constriction Relaxation
Ureters	Increase motility	a	Increase?
Uterus	Variable Contraction	a, b2	Variable
Male Sex organs	Ejaculation	a	Erection
Sweat glands	Localised secretion		Generalised secretion
Secretions Salivary	Vasoconstriction Thick, viscous secretion	a	Copious and watery
Pancreatic	Decreased secretion ¯ insulin & glucagon secretion	a b	Increased secretion ­insulin & glucagon Secretion
Gastric	viscous secretion		­secretion
Juxtaglomerular cells	Increased renin secretion	b	--
Pineal gland	Increased melatonin secretion	b	--
Milk letdown	Inhibition		--
Ciliary muscle	Relaxation (far vision)	b	Constriction (near vision)
Pupillary muscle	Dilatation (dim light)		Constriction (bright light)
BMR	Increased		---