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Summary. The experiments reported here demonstrate for the first time that the isolated testicular capsule of the rat is capable of undergoing marked contraction following exposure to acetylcholine, carbachol, pilocarpine, norepinephrine, epinephrine, histamine and tetramethylammonium. Isoproterenol produces a relaxation of the isolated capsule but barium ions have essentially no effect at physiological doses.
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Davis et al. (1969) studied this question.
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