Comparative effects of growth hormone on water and ion transport in rat jejunum, ileum, and colon

  title={Comparative effects of growth hormone on water and ion transport in rat jejunum, ileum, and colon},
  author={Roberto Berni Canani and Michele Iafusco and Rosario Russo and Massimo Bisceglia and Gaetano Polito and Alfredo Guarino},
  journal={Digestive Diseases and Sciences},
Specific growth hormone (GH) receptors are located along the entire rat intestine. We have recently shown that GH induces water and ion absorption in the rat ileum. This raises the possibility that GH regulates water and ion transport throughout the intestine. To test this, we have evaluated the effects of GH administration on jejunal, ileal, and colonic water and ion transport, by thein vivo rat perfused intestine, andin vitro, in corresponding segments of intestine mounted in Ussing chambers… 
Postreceptor resistance to exogenous growth hormone exists in the jejunal mucosa of parenterally fed rats.
The lack of early c-fos and c-jun induction in response to GH in TPN rats indicates that the jejunal mucosa is resistant to exogenous GH between GHR activation and induction of immediate early genes, which may contribute to the inability of mucosal cells to respond to the trophic effects of GH.
Discrepancies Between Effects of Recombinant Human Growth Hormone on Absorption and Secretion of Water and Electrolytes on the Human Jejunum Compared to Results Reported on Rat Jejunum
Rec recombinant human growth hormone cannot be considered a useful proabsorptive antidiarrheal agent in humans and is most likely due to the species difference rather than to differences in methods that were used.
Growth hormone regulates intestinal ion transport through a modulation of the constitutive nitric oxide synthase-nitric oxide-cAMP pathway.
The results suggest that the GH effects on intestinal ion transport, either under basal conditions or in the presence of cAMP-stimulated ion secretion, are mediated at an intracellular level by the activity of cNOS.
Osmoregulation and epithelial water transport: lessons from the intestine of marine teleost fish
  • J. Whittamore
  • Environmental Science
    Journal of Comparative Physiology B
  • 2011
An assessment of the teleost intestine as a fluid-transporting epithelium is presented, with particular attention given to acid–base transfers by the intestine, which creates the distinctly alkaline gut fluids responsible for the formation of solid calcium carbonate precipitates.
Effect of exercise on key pharmacokinetic parameters related to metformin absorption in healthy humans: A pilot study
The results provide the first evidence that pharmacokinetic values related to metformin absorption are affected by exercise, and did not cause hypoglycemia or lactic acidosis.


In Vivo and In Vitro Effects of Human Growth Hormone on Rat Intestinal Ion Transport
The results indicate that hGH has a rapid absorptive effect that is related, at least in part, to a direct intestinal antisecretory mechanism and it also reduces active intestinal secretion induced by various secretagogues.
Effects of bovine growth hormone, human placental lactogen and ovine prolactin on intestinal fluid and ion transport in the rat.
Growth hormone and human placental lactogen appear to affect jejunal water and electrolyte transport in the same manner as occurs with prolactin, possibly by influencing active ion transport.
Na+-K+-activated adenosine triphosphatase and intestinal electrolyte transport. Effect of adrenal steroids.
Methylprednisolone and DOCA increased electrolyte and water transport and Na-K-ATPase activity concomitantly in specific segments of small intestine and colon, consistent with an important role for Na- K- ATPase in intestinal electrolyteand water transport.
Growth hormone receptor expression in the rat gastrointestinal tract.
D discrete epithelial cell subpopulations of the GIT and its derivatives are directly responsive to GH action and GH may, therefore, act independently of or synergistically with hepatic insulin-like growth factor-I in executing its physiological and/or growth-promoting role in the G IT.
Assessment of mineralocorticoid activity in the rabbit colon.
  • D. Marver
  • Biology, Medicine
    The American journal of physiology
  • 1984
Findings would suggest that the rabbit distal colon is a target segment for both mineralocorticoids and glucocorticaoids, and as in the kidney, the two steroids may play coordinated but, perhaps in some way, unique roles in the regulation of transport.
Stimulation by Recombinant Human Growth Hormone of Growth and Development of Remaining Bowel After Subtotal Ileojejunectomy in Rats
In conclusion, GH improves the postoperative intestinal adaptation process in terms of both weight gain and small bowel lengthening in women weaning female Wistar rats.
Recombinant human growth hormone enhances the metabolic efficacy of parenteral nutrition: a double-blind, randomized controlled study.
GH was well tolerated and significantly enhanced nutrient retention compared to standard parenteral feeding alone and in contrast, nutrient balances did not change significantly from baseline values in control patients.
An evaluation of perfusion techniques in the study of water and electrolyte absorption in man: the problem of endogenous secretions.
Both methods gave simiar quantitative rates of water and sodium absorption, suggesting that contamination is negligible in normal fasting upper jejunum, however, absorption of solute and water by the proximal segment of the triple-lumen tube apparatus produced difficulties in experimental technqiue.
Pharmacokinetics and short-term metabolic effects of mammalian cell-derived biosynthetic human growth hormone in man.
The pharmacokinetics and acute effects of an authentic recombinant DNA-derived human growth hormone (rhGH) produced by genetically engineered mammalian cells were determined in 12 healthy volunteers following intravenous, intramuscular and subcutaneous administration, and local and systemic tolerance were good, and no adverse reactions were observed.