Effect of Insulin and Alloxan Diabetes on Carrageenin Inflammation in Rats

Abstract

Some hypersensitivity reactions and allergic responses are known to be increased by insulin treatment and decreased in diabetes. In contrast, the present experiments showed that paw swelling induced by carrageenin in rats was inhibited by insulin. The anti-inflammatory activity, to some extent, paralleled the dose applied and did not appear to be due to hypoglycaemia. Alloxan diabetes in turn increased the vascular response to carrageenin and abolished the anti-inflammatory effect of insulin. The experiments call attention to the possible significance of insulin in the regulation of the acute non-immune inflammatory process.

Anaphylactoid Reactions in Rats and the Blood Sugar Level

“…Blood sugar values in both types of rat were similar, confirming that NR rats are not diabetic (table I). After insulin (10 IU/kg) when the blood sugar level in R rats had been reduced by about 50%>, the carrageenan response was significantly reduced (p<0.05), thereby confirming the results of Ottlecz et al [1976]. NR rats responded similarly though the inhibition of the carrageenan reaction by insulin was much greater ( fig.…”

“…Recently, Ottlecz et al [1976] reported that sensitivity of R rats to carrageenan was decreased by insulin and we decided to compare the responses of R rats to the simultaneous administration of dextran and carrageenan in hypoglycaemic and hyperglycaemic states with those of NR rats un der similar conditions, and so provide more valuable information about the resistance of NR rats to systemic dextran.…”

Contributions to the Regulatory Role of Insulin in Inflammation and Anaphylaxis

“…The anti-inflammatory effect of the hormone was found to be dose-dependent and more effective at the 2nd hour after the injection of the phlogogen than at the 4th hour of swelling when less inhibition and a bell-shaped dose-response curve was ob served. These findings are in agreement with our previous results obtained in Sprague-Dawley CFY rats [Ottlecz et al, 1976[Ottlecz et al, , 1977a, 5-HT edema was only mildly re duced by these insulin doses, although high er amounts exerted a pronounced anti-in flammatory effect. This finding is in accord with that reported by Church et al [1974], The observations reported here suggest that insulin may play a complex regulatory role in the release of anaphylactic and in flammatory mediators not only in rats but also in mice.…”

Anaphylactoid Responses in Rats

“…Lymphotoxic drugs also inhibit the potentiating action of insulin. In the present work, insulin fails to assist in the production of an anaphylactoid reaction to dextran, mannan or ovomucoid in NR rats although there is hypoglycaemia [see Harper and West, 1976], Major differences between the carra geenan and dextran responses in R rats were reported by Ottlecz et al [1976] when they showed that insulin reduces the carra geenan response and alloxan treatment in creases it, the opposite of the effects on the dextran response. So, there are at least three classes of agents capable of producing an anaphylac toid response in rats: (1) those like dextran, mannan and ovomucoid which arc active only in R rats and which are potentiated by insulin; (2) those like Con A which are ac tive only on subcutaneous injection into R rats and which arc potentiated by insulin, and (3) those like carrageenan which are ac tive on subcutaneous injection into both R and NR rats and which are reduced by insu lin.…”