The purpose of this investigational study is to find out what hormones are present in healthy male testicles using fine needle aspiration.

We will collect a very small amount of fluid from each testicle. Participation will last up to 12 weeks. The study involves a minimum of 4 visits, the screening visit and procedure Day, fine needle aspiration of the testes (about 1-1.5 hours each) and two follow-up visits (about 30-45 minutes). Over the course of the study, you will have a little less than a 1/3-cup of blood drawn (roughly 2-3 tablespoons at each visit).

Inclusion Criteria:

• males between 18 and 50 years of age
• sperm count greater than 20 million/ml, greater than 50% motility, and greater than 15% normal morphology
• in good general health based on normal screening evaluation (consisting of a medical history, physical exam, normal sperm count, normal serum chemistry, hematology and baseline T, LH, and FSH levels)
• body mass index ≥18 and ≤32 kg/m2
• must agree not to participate in another research study involving drug exposure for the duration of the study

Exclusion Criteria:

• men in poor general health, with abnormal blood results
• sperm counts <20 million/ml on two tests
• chronic, ongoing alcohol or drug abuse
• participation in a long-term male contraceptive study within the past three months
• history of testicular or scrotal surgery
• history of infertility
• abnormal testicular exam
• abnormal DRE
• chronic pain syndrome
• use of steroids, testosterone, or medications which might interfere with androgen metabolism including ketoconazole, glucocorticoids
• known bleeding disorder
• use of medications which may affect bleeding time (ongoing aspirin or anti-inflammatory use, coumadin)

Healthy males

4 months

The first subject was screened 9/26/2008; the last subject exited 1/16/2009. Subjects in the study are asked about adverse events and concomitant medications at every visit.

Early termination of study leading to data analysis of the first ten of eleven men receiving aspirations.