Pharmacological properties of Go. 7996B (Varsyl)
Grewal, R.S.; Kaul, C.L.; David, J.
Indian Journal of Experimental Biology 19(8): 733-737
1981
ISSN/ISBN: 0019-5189 PMID: 7309157 Document Number: 174304
Pharmacological properties of a new, potent and long acting vasoconstrictor agent, i.e., 4,5-dihydro-2-(3-indolyl) mercaptominidazole hydrochloride (G. 7996B, Varysyl), potentially useful as a nasal decongestant are described. The vasoconstrictor effects were demonstrated in different species on various vascular beds. In dog, the vasoconstrictor effect of the compound on nasal vascular bed was studied by rhinomanometric methods, temperature recording and by measuring changes in nasal resistance and on the total vascular bed by blood pressure recording. The vasoconstrictor effect of Go. 7996B was studied on the isolated hind limb preparation in cat. Changes in the nasal resistance are measured in the guinea pig. Go. 7996B has no deleterious effects on ciliary movement and it produces its vasoconstrictor effect by stimulation of .alpha.-adrenoceptors and has no .beta.-adrenoceptor activity. The compound shows good CNS tolerability. Go. 7996B is a potent vasoconstrictor and is 8-12 times more active than xylometazoline, 4-15 times more active than naphazoline and 3-4 times more active than oxymetazoline in different test systems. It has the longest duration of action of all clinically used nasal decongestants.