Effect of topical antiglaucoma drugs on corneal epithelium wound healing in rabbits

Topical antiglaucoma drugs had been used frequently in treatment of different types of glaucoma. Some of these drugs cause inhibition of corneal epithelial wound healing. So, this study aimed to determine the toxic effect of topical antiglaucoma drugs on corneal epithelium of the rabbit. In the present study, seven antiglaucoma drugs [[1] Timolol maleate 0.5%; [2] Apraclonidine HCI 0.5%; [3] Dipvefrin HCI 0.1%; [4] Betoxolol HCI 0.5% [5] Levobunolol HCI 0.5%, [6] Befunolol HCI 0.5%, and [7] Pilocarpine HCI 2%] in their therapeutic concentrations were applied to the cornea of the rabbit which undergone mechanical removal of the epithelium 8 mm in diameter.The rate of healing of conreal wound in saline treated controls was found significant if compared with antiglaucoma drugs.Drugs 5,6,7 demonstrated more rapid healing than drugs 1, 2, 3, 4. In this study, anti glaucoma drugs appear to have toxic effect on the corneal epithelial wound healing specially drug 2 followed by drugs 1, 3, 4

Influence of beta-adrenoceptor antagonists on spontaneous rate and on force of contraction of isolated rabbit atria.

The influence of beta-adrenoceptor antagonists on the spontaneous rate and on force of contraction of the myocardium was studied independently on spontaneously beating right and electrically driven isolated left atria of rabbit. On spontaneous rate, practolol had sympathomimetic effect only, N-isopropylmethoxamine (IMA), had both sympathomimetic as well as depressant effects, whereas alprenolol, procinolol, bunolol and H 35/25 had depressant effects only in higher concentrations. The order of potency was procinolol greater than bunolol greater than alprenolol greater than H 35/25 greater than and IMA. On the contractions of isolated left atria, all beta-adrenoceptor antagonists produced concentration-dependent depressant effect. In relation to procinolol, these agents were 5-125 times less potent for depressing the contractions of left atria by 15% and the order of beta-potency was procinolol greater than alprenolol greater than bunolol = H 35/25 greater than IMA greater than and practolol. The present results indicate that the depressant effects of beta-adrenoceptor antagonists on spontaneous rate of right atria and on contraction of isolated left atria are not related to each other.