| Abstract: | In physiological concentrations myo-inositol stimulated production of prostaglandin (PG)-like material in a rat mesenteric vascular bed preparation. There were five lines of evidence: 1. Inositol potentiated pressor responses to both norepinephrine and potassium in a manner similar to PGE2. 2. Inositol had no potentiating effect in preparations in which endogenous PG production was blocked by indomethacin. 3. Inositol caused no further potentiation in preparations already potentiated by arachidonic acid, the PG precursor. 4. The inhibitory effect of the PG antagonist chloroquine was reduced in an apparently competitive manner by inositol. 5. As indicated by rat stomach bioassay inositol caused a three fold rise in the outflow of PG-like material from the preparation. |
