Effects of dietary vitamin D deficiency on the cardiovascular system.
Experiments were performed on normotensive rats exposed to vitamin D deficient and control diets from the 22nd to the 180th day of age. In 60-120- and 180-day-old rats. The following parameters were evaluated: a) The vasomotor responses elicited by receptor agonists in the absence and in the presence of the respective antagonists [L-norepinephrine (NE) before and 5 min after prazosin; L-isoprenaline (I) before and 5 min after DL-propranolol; L-dopamine (DA) before and 5 min after L-sulpiride or SCH 23390 or chlorpromazine; acetylcholine (Ach) before and 5 min after atropine; histamine (H) before and after chlorpheniramine; 5-hydroxytryptamine (5-HT) before and 5 min after methysergide or ketanserin]; by carotid-sinus baroreceptor stimulation (CO) before and 5 min after hexamethonium, and by electrical stimulation of the vagus peripheral head (V) before and after atropine; b) Reflex tachycardia elicited by bilateral carotid occlusion (CO) (for 40 sec) and by sodium nitroprusside; c) Catecholamine (norepinephrine, epinephrine) and arginine-vasopressin plasma levels; d) Cholesterol, triglyceride and electrolyte (Na+, K+, Cl-, Ca2+) serum levels. Our results showed that vitamin D deficient diets induced a decrease in pressor responses to NE and CO, and an increase in hypotensive responses to I, DA, Ach, H, 5-HT and V. Changes of arterial blood pressure, heart rate, catecholamine and arginine-vasopressin plasma levels were not observed. Cholesterol, triglyceride and electrolyte (Na+, K+, Cl-) serum levels were not modified, while Ca2+ serum levels decreased. In conclusion, our data suggest that vitamin D depletion can induce changes of pressor and depressor vasomotor responses and suppose a direct role for vitamin D in regulating vasomotor reactivity.
De Novellis
V
V
Institute of Pharmacology and Toxicology, II University of Naples, Italy.
Loffreda
A
A
Vitagliano
S
S
Stella
L
L
Lampa
E
E
Filippelli
W
W
Vacca
C
C
Guarino
V
V
Rossi
F
F
D000818:Animals; D001794:Blood Pressure; D002118:Calcium / Q000097:blood; D002395:Catecholamines / Q000097:blood; D002784:Cholesterol / Q000097:blood; D004558:Electric Stimulation; D004573:Electrolytes / Q000097:blood; D005260:Female; D006339:Heart Rate; D008297:Male; D011311:Pressoreceptors / Q000502:physiology; D051381:Rats; D014280:Triglycerides / Q000097:blood; D014666:Vasomotor System / Q000502:physiology*; D014808:Vitamin D Deficiency / Q000378:metabolism / Q000503:physiopathology*
D002395:Catecholamines; D004573:Electrolytes; D014280:Triglycerides; D002784:Cholesterol; D002118:Calcium