{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,2,5]],"date-time":"2026-02-05T20:24:17Z","timestamp":1770323057540,"version":"3.49.0"},"reference-count":21,"publisher":"American Veterinary Medical Association (AVMA)","issue":"2","content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["ajvr"],"published-print":{"date-parts":[[2018,2]]},"abstract":"<jats:title>Abstract<\/jats:title>\n<jats:p><jats:bold>OBJECTIVE<\/jats:bold> To assess insulin, glucagon, and somatostatin expression within pancreatic islets of horses with and without insulin resistance.<\/jats:p>\n<jats:p><jats:bold>ANIMALS<\/jats:bold> 10 insulin-resistant horses and 13 insulin-sensitive horses.<\/jats:p>\n<jats:p><jats:bold>PROCEDURES<\/jats:bold> For each horse, food was withheld for at least 10 hours before a blood sample was collected for determination of serum insulin concentration. Horses with a serum insulin concentration &lt; 20 \u03bcU\/mL were assigned to the insulin-sensitive group, whereas horses with a serum insulin concentration &gt; 20 \u03bcU\/mL underwent a frequently sampled IV glucose tolerance test to determine sensitivity to insulin by minimal model analysis. Horses with a sensitivity to insulin &lt; 1.0 \u00d7 10<jats:sup>\u22124<\/jats:sup> L\u2022min<jats:sup>\u22121<\/jats:sup>\u2022mU<jats:sup>\u22121<\/jats:sup> were assigned to the insulin-resistant group. All horses were euthanized with a barbiturate overdose, and pancreatic specimens were harvested and immunohistochemically stained for determination of insulin, glucagon, and somatostatin expression in pancreatic islets. Islet hormone expression was compared between insulin-resistant and insulin-sensitive horses.<\/jats:p>\n<jats:p><jats:bold>RESULTS<\/jats:bold> Cells expressing insulin, glucagon, and somatostatin made up approximately 62%, 12%, and 7%, respectively, of pancreatic islet cells in insulin-resistant horses and 64%, 18%, and 9%, respectively, of pancreatic islet cells in insulin-sensitive horses. Expression of insulin and somatostatin did not differ between insulin-resistant and insulin-sensitive horses, but the median percentage of glucagon-expressing cells in the islets of insulin-resistant horses was significantly less than that in insulin-sensitive horses.<\/jats:p>\n<jats:p><jats:bold>CONCLUSIONS AND CLINICAL RELEVANCE<\/jats:bold> Results suggested that, in insulin-resistant horses, insulin secretion was not increased but glucagon production might be downregulated as a compensatory response to hyperinsulinemia.<\/jats:p>","DOI":"10.2460\/ajvr.79.2.191","type":"journal-article","created":{"date-parts":[[2018,1,23]],"date-time":"2018-01-23T16:31:32Z","timestamp":1516725092000},"page":"191-198","source":"Crossref","is-referenced-by-count":7,"title":["Immunohistochemical expression of insulin, glucagon, and somatostatin in pancreatic islets of horses with and without insulin resistance"],"prefix":"10.2460","volume":"79","author":[{"given":"Kim 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