Influence of intracerebroventricular phenoxybenzamine on the renal action of intracerebroventricular morphine.
Renal function is under regulatory influence of the central nervous system, either through mediation of humoral agents or by way of renal nerves, with the sympathetic nerve playing the most important role. As it was recently shown that morphine and enkephalin, when administered intracerebroventricularly (icv), affect renal function in the rabbit, indicating that the opiate receptors are also involved in the central regulation of renal function, it was attempted to clarify whether the central adrenergic system participates in the center-mediated renal action of morphine, employing phenoxybenzamine (PBZ). Morphine, 10 micrograms/kg icv, produced profound and long-lasting antidiuresis and antinatriuresis. PBZ, 250 micrograms/kg icv, elicited marked diuresis with natriuresis and kaluresis, along with significant increases of osmolar clearance and free-water reabsorption, and these effects were not related to a transient increase in glomerular filtration. When PBZ was given 10 min after morphine, the morphine antidiuresis immediately disappeared and the renal action of PBZ unfolded itself undiminished. Also, when morphine was given after PBZ, the PBZ-diuresis developed fully, unaffected by morphine. These observations indicate that the central adrenergic system is involved in the regulation of renal function through central opiate receptors.
Kook
Y J
YJ
Choi
B K
BK
Yoo
K Y
KY
Kim
K H
KH
D000818:Animals; D004231:Diuresis / Q000187:drug effects; D005260:Female; D005919:Glomerular Filtration Rate / Q000187:drug effects; D007276:Injections, Intraventricular; D007668:Kidney / Q000187:drug effects*; D007671:Kidney Concentrating Ability / Q000187:drug effects; D008297:Male; D009020:Morphine / Q000008:administration & dosage* / Q000037:antagonists & inhibitors; D010643:Phenoxybenzamine / Q000008:administration & dosage* / Q000494:pharmacology; D011817:Rabbits; D011957:Receptors, Opioid / Q000502:physiology
D011957:Receptors, Opioid; D010643:Phenoxybenzamine; D009020:Morphine