The Delivery of Testosterone and Dihydrotestosterone by ALCAP Ceramic Implants in Rats

Abstract

The objectives of this investigation were to evaluate the release of testosterone (T) and dihydrotestosterone (DHT) from nonimpregnated and polylactic acid (PLA) impregnated ALCAP ceramic reservoirs implanted in rats, and to study the effects of delivered androgens on the reproductive system of male rats. A total of 120 Sprague-Dawley albino male rats were distributed equally into three groups. Two ALCAP capsules, one nonimpregnated and the other impregnated with PLA, were implanted into each rat in groups I and II. Capsules implanted into group I rats were loaded with a mixture of 20 mg T and 20 mg DHT. Group II rats were implanted with two empty capsules (sham group), and group III animals served as unimplanted controls. Eight rats from each group were euthanized at the end of 3, 6, 9, and 12 months following the implantation of the ceramics. No significant change in the weights of vital organs of rats was observed among any of the three different groups. Vas deferens and epididymal fluid were devoid of normal spermatozoa within 3 months of implanting the steroid-containing ceramics. Testicular weights decreased significantly in the rats implanted with ALCAP containing steroids and the seminiferous tubules became oligospermic after 1 month and azoo-spermic after 3 months. The data collected in this study suggest that (1) ALCAP ceramic capsules are capable of delivering T and DHT in combined form, and (2) T and DHT delivered by ALCAP capsules can be used effectively to regulate spermatogenesis in rats.

Key Words:

• ALCAP
• ceramics
• drug delivery systems
• androgens
• testosterone
• dihydrotestosterone
• implantable devices