Pentagastrin stimulates potassium absorption from the rat colon.
Pentagastrin is trophic to the colon but the physiologic effects of pentagastrin are incompletely known. We compared in vivo potassium (K+) absorption from the colons of pentagastrin-treated (PG, n = 13), sham (S, n = 12), and control (C, n = 3) Sprague-Dawley rats during continuous intraluminal K+ perfusion. Preoperative intraperitoneal injections were administered to PG (pentagastrin 0.25 mg/kg in 2 mL 0.9% NaCl q 12 h x 48 h) and S (2 mL 0.9% NaCl q 12 h x 48 h). Under xylazine anesthesia, cannulae were placed in the cecum, rectum, and femoral artery of each rat. Intraluminal perfusion was performed for 2 h at 30 mL/min with 40 meq/L KCl in 0.9% NaCl (PG and S) or 0.9% NaCl (C). We monitored serum sodium (Na+) and K+ every 15 min, and the affluent and effluent Na+ and K+ every 30 min. At each interval past 60 min, we observed higher serum K+ in PG compared with S and C (P less than .002) and higher K+ in S compared with C (P less than .05). No changes in serum Na+ occurred. We conclude that pentagastrin stimulates potassium absorption from the colon.
Lovett
J V
JV
Department of Surgery, University of Nevada School of Medicine, Reno 89520.
McGregor
D B
DB
D000818:Animals; D003106:Colon / Q000502:physiology*; D007408:Intestinal Absorption / Q000187:drug effects*; D008297:Male; D010418:Pentagastrin / Q000494:pharmacology*; D011188:Potassium / Q000097:blood / Q000378:metabolism*; D051381:Rats; D011919:Rats, Inbred Strains
D010418:Pentagastrin; D011188:Potassium