Prostaglandins

Karmazyn, Horrobin, Morgan, Manku, Ally and Karmali, IRCS Medical Science (1977),¹⁹²¹ studied norepinephrine-induced, prostaglandin-dependent vasoconstriction in the rat mesenteric vascular bed. PHT produced a dose-dependent inhibition (50% at 10 µg/ml) of the vasoconstriction response to norepinephrine (10 ng) and potassium chloride (2 mg). In other experiments PHT competitively inhibited the vasoconstrictive effects of prostaglandin E₂. The authors suggest that PHT's effects on Prostaglandins may explain its usefulness in many clinical disorders including cardiovascular and muscle disorders, pain, asthma, and endocrine and neural dysfunctions. See also Ref 2660.

1921. Karmazyn, M., Horrobin, D. F., Morgan, R. O., Manku, M. S., Ally, A. I. and Karmali, R. A., Diphenylhydantoin: a prostaglandin antagonist in the rat mesenteric vasculature, IRCS Medical Science, 5: 332, 1977.
2660. Khan, M. T., Studies on the uterine inhibitory actions of diphenylhydantoins, Arch. Int. Pharmacodyti. Ther., 260: 265-73,1982.

Katsumata, Gupta, Baker, Sussdorf and Goldman, Science (1982),²⁶⁵¹ reported that, in mice, both PHT and glucocorticoids, through a common receptor, inhibit formation of 6-ketoprostaglandin F₁ and thromboxane B₂ which are the stable metabolites of prostacyclin and thromboxane A₂. See also Ref 2561.

2651. Katsumata, M., Gupta, C., Baker, M. K., Sussdorf, C. E., Goldman, A. S., Diphenylhydantoin: an alternative ligand of a glucocorticoid receptor affecting prostaglandin generation in A/J mice, Science, 218: 1313-15, 1982.

2561. Gupta, C., Katsurnata, M., Goldman, A. S., H-2 histocompatibility region influences the inhibition of arachidonic acid cascade by dexamethasone and phenytoin in mouse embryonic palates, J. Craniofac. Genet. Dev. Biol., 5: 277-85, 1985.

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