A possible mechanism for the detrimental effect of varicocele on testicular function in man

Effect of Varicocele and Its Treatment on Testosterone in Hypogonadal Men with Varicocele: Review of the Literature

Varicocele might cause deterioration in Leydig cell functions, and it is a significant risk factor for hypogonadism. Some controversial issues have been raised in the treatment of hypogonadal men with varicoceles. Symptomatic hypogonadal men with varicoceles have two options: testosterone replacement therapy or varicocele treatment. Both approaches have some advantages and disadvantages. This review summarizes the effect of varicoceles on total plasma testosterone level and addresses whether varicocele repair is effective to improve testosterone levels in hypogonadal men with varicoceles. Experience from large clinical studies in the literature suggests that varicocele repair may increase serum testosterone level in men with varicoceles and testosterone deficiency. Varicocele repair could be offered to men with clinically palpable varicocele and hypogonadism. As the treatment method, microsurgical varicocele repair could be preferred to provide the best improvement. Another advantage of varicocele repair for hypogonadism, instead of exogenous testosterone treatment, is its ability to preserve the fertility status in men who may desire a child in the future. However, further studies are required to clarify varicocel-related Leydig cell dysfunction and to advise hypogonadal patients about the sufficient effectiveness of varicocele repair.

Extended indications for varicocelectomy

The relationship between varicoceles and subfertility is well-established, but recent evidence suggests that varicoceles may cause global testicular dysfunction. This has led to exploration into expanding the indications for varicocelectomy. This review examines the literature regarding varix ligation as a treatment for non-obstructive azoospermia, elevated DNA fragmentation, and hypogonadism.

Treatment strategy for the adolescent varicocele

A varicocele is a dilatation of the testicular vein and the pampiniform venous plexus within the spermatic cord. Although rare in pediatric populations, the prevalence of varicoceles markedly increases with pubertal development. Varicoceles are progressive lesions that may hinder testicular growth and function over time and are the most common and correctable cause of male infertility. Approximately 40% of men with primary infertility have a varicocele, and more than half of them experience improvements in semen parameters after varicocelectomy. The decision to treat adolescents with varicocele is a controversial one. The task for pediatricians and urologists is to identify those adolescents who are at greatest risk for infertility in adulthood, in an effort to offer early surgical intervention to those most likely to benefit.

VARICOCELE LIGATION ON FREE TESTOSTERONE LEVELS IN INFERTILE MEN WITH VARICOCELE

We have analyzed the effects of varicocele ligation on free testosterone levels, and investigated the interrelationships between free testosterone and fertility. The records were retrospectively evaluated for 42 infertile patients who underwent varicocele ligation, with serum free testosterone levels, follicle stimulating hormone (FSH), lutenizing hormone (LH), testosterone, estradiol, prolactin, ejaculated volume, sperm concentration and motility before and after surgery. Serum free testosterone levels increased from 12.97+/-4.16 to 13.59+/-3.93 pg/mL, but the difference was insignificant. The differences before and after surgery of patients in sperm concentration and motility were also insignificant. However, in free testosterone increasing group, the sperm concentration and motility increased significantly, from 4.05+/-4.35 to 7.90+/-8.19 million/mL (P=0.01) and from 30.64+/-21.87% to 41.00+/-22.00%, respectively (P=0.03). The increase in serum free testosterone level by varicocele ligation results in a significant improvement in sperm concentration and motility.

Elevation of serum testosterone and free testosterone after embolization of the internal spermatic vein for the treatment of varicocele in infertile men

BACKGROUND

To evaluate the effect of internal spermatic vein (ISV) embolization on levels of serum testosterone and free testosterone and on spermatogenesis.

METHODS

The files of 83 infertile men treated for varicocele were reviewed for changes in serum testosterone, free testosterone and spermatogenesis after ISV embolization.

RESULTS

Mean serum testosterone concentration rose after embolization by 43%, from 12.07 +/- 6.07 nmol/l to 17.22 +/- 8.43 nmol/l (P<0.001). Mean serum free testosterone concentration rose by 72%, from 5.93 +/- 2.44 nmol/l to 10.21 +/- 7.69 nmol/l (P<0.001). Mean sperm concentration increased from 7.49 +/- 1.73 x 10(6)/ml to 18.14 +/- 2.36 x 10(6)/ml (P<0.001); mean sperm motility increased from 21.74 +/- 2.47 to 34.47 +/- 2.27% (P<0.001); and mean sperm morphology increased from 6.63 +/- 1.07 to 13.08 +/- 1.44% (P<0.001).

CONCLUSIONS

ISV embolization apparently induces an increase in both serum testosterone and free testosterone concentrations and in sperm parameters in infertile patient with varicocele, regardless of the size of the varicocele.

The adolescent varicocele: to treat or not to treat

Whether to treat adolescents with varicocele is controversial because over 80% of adult varicoceles are not associated with infertility. Most physicians agree that treating all adolescents with varicocele and subjecting boys to unnecessary surgery is inappropriate,costly, and not without ethical considerations. Waiting until patients present as adults with potentially irreversible infertility, however, is equally unacceptable. Pediatricians and urologists must determine which adolescents are at greatest risk for future fertility problems and warrant early intervention. This article reviews the current literature surrounding adolescent varicocele and offers recommendations for identifying individuals who would most benefit from treatment.

Increased serum inhibin B levels after varicocele treatment

OBJECTIVE

Inhibin B is secreted by Sertoli cells in response to FSH and is the major feedback regulator of FSH secretion in man. The serum inhibin B level has emerged as a good marker of spermatogenesis and Sertoli cell function. Varicocele has been associated with infertility and disturbed spermatogenesis. We have studied the effect of varicocele treatment on serum inhibin B levels, with the aim of investigating the effect on spermatogenesis and the involvement of the Sertoli cell in varicocele pathophysiology.

DESIGN AND PATIENTS

In a pre-post test design, the effect of varicocele surgery on inhibin B levels was studied in 30 infertile men.

MEASUREMENTS

Endocrinology (inhibin B, FSH, LH, SHBG and testosterone) and semen analysis (sperm concentration, motility and morphology).

RESULTS

In men receiving varicocele treatment, a significant increase in serum inhibin B levels was observed from 133.9 +/- 13.4 pretreatment to 167.8 +/- 16.1 ng/l after treatment (mean +/- SEM, P < 0.0001). No significant changes were observed in serum levels of FSH, LH and testosterone. The serum SHBG level decreased from 32.9 +/- 3.5 to 28.6 +/- 3.4 nmol/l (mean +/- SEM, P = 0.04) and the free androgen index was significantly increased from 66 +/- 5.9 pretreatment to 85 +/- 6.8 after treatment (P = 0.02, mean +/- SEM). Semen analysis showed a significant improvement in sperm concentration, from 6.5 +/- 1.9 pretreatment to 19.3 +/- 4.9 x 106/ml after treatment (P = 0.003, mean +/- SEM), and in sperm motility from the baseline level of 17 +/- 3 to 32 +/- 4% after treatment (P = 0.001, mean +/- SEM).

CONCLUSIONS

Varicocele treatment can increase serum inhibin B levels, indicating improvement of spermatogenesis and Sertoli cell function. This finding suggests that the pathophysiology of varicocele involves impairment of Sertoli cell function or a different distribution of germ cell stages.

Low plasma testosterone in varicocele patients with impotence and male infertility

To study the affect of bilateral varicocele (grade 3) on impotence and male infertility patients, 29 patients were selected from an outpatient clinic during 15 May 1998 to 15 August 1999 (the mean age was 33.9 +/- 6.3), 15 patients complaining of erectile dysfunction and 14 patients complaining of male infertility. The mean duration of impotence was 3 +/- 2.3 years and for male infertility was 6 +/- 2.5. All organic and psychogenic causes related to impotence and male infertility except bilateral varicocele (grade 3) and low plasma testosterone were excluded by clinical and laboratory investigations. Twenty males with normal erection and fertility were included as controls. Detailed medical history and complete physical examination included measurement of testicular size by orchiometer; semen and hormonal parameters were measured for all patients and control. In impotent patients left and right testicular volume was significantly decreased (p < .05), while in male infertility patients left and right testicular volume was highly significantly and, significantly decreased (p < .005, p < .05) compared to controls. In male infertility patients, left testicular volume was highly significantly decreased compared to impotent patients (p < .005). The sperm count and semen volume in impotent patients was significantly decreased (p < .05, p < .01), but no significant differences were found in sperm motility and abnormal forms, while in male infertility the sperm count was highly significantly decreased (p < .005), the sperm motility was significantly decreased (p < .05), the abnormal form was significantly increased (p) < .05), but in the semen volume there was no significant difference compared to controls. In impotent patients the sperm count was significantly increased and abnormal form was significantly decreased compared to male infertility (p < .05). The mean serum testosterone was significantly decreased in impotent patients (p < .01), and highly significantly decreased in male infertility (p < .005) compared to controls. The mean serum FSH was significantly increased in male infertility (p < .05) and nonsignificant in impotent patients compared to controls. The mean serum LH and prolactin levels were nonsignificant in both impotent and male infertility patients compared to controls, but LH was significantly increased in impotence compared to male infertility patients (p < .025). Therefore, bilateral varicocele (grade 3) is associated with significant reduction in testicular function with significant increase in serum levels of FSH and LH, which may cause erectile dysfunction and male infertility.

Evaluation of the relationship between semen parameters, pregnancy rate of wives of infertile men with varicocele, and gonadotropin-releasing hormone test before and after varicocelectomy

OBJECTIVES

To determine whether the gonadotropin-releasing hormone (GnRH) test can serve as an indicator for the need and timing of surgery in infertile men with varicocele.

METHODS

The GnRH test was performed in 121 infertile men with varicocele before surgical correction and 4 to 6, 9 to 12, and 16 to 18 months after. Levels of follicle-stimulating hormone (FSH) and luteinizing hormone (LH) were evaluated immediately before the test and 45 minutes after intravenous injection of 100 jig Relisorm L (a synthetic GnRH analogue). Eighteen fertile men with normal semen parameters served as control patients for defining the preoperative hormone levels. A more than twofold increase in FSH and a more than fivefold increase in LH was considered a positive result. Findings were correlated with semen parameters and rate of pregnancy in the patients' wives at 18 months postoperatively.

RESULTS

Of the 121 patients, 89 (73.5%) had a positive GnRH test result, and 32 had a negative result. Semen parameters were improved postoperatively in 72 of the GnRH-positive patients (80.9%) and in only 6 of the GnRH-negative patients (1 8.7%). Corresponding pregnancy rates at 18 months in the two subgroups were 60 (67.4%) and 3 (9.3%), respectively.

CONCLUSIONS

A positive preoperative GnRH test is a good predictor of improvement in semen parameters and pregnancy after varicocele surgery. We suggest that the GnRH test can serve as an additional indicator for varicocelectomy.

The significance of gonadotropin-releasing hormone test for predicting fertility after varicocelectomy

To predict the surgical outcome in 30 infertile men with varicocele, endocrinologic evaluation by the GnRH test was performed before and 6 months after the high ligation of the left internal spermatic vein. Semen analysis was performed and the levels of basal T and PRL were examined preoperatively and 6 months postoperatively. In the pregnancy group, the preoperative excessive response of LH to the GnRH test decreased significantly after surgery. Significant reduction in the LH response is considered to be a valuable parameter for predicting fertility.

Restoration of spermatogenesis and subsequent fertility by direct intratesticular hormonal therapy

Testosterone-laden microspheres (TLM) were used in an attempt to restore spermatogenesis and sustain fertility in rats with previously suppressed gonadal function. Adult rats received 62.5 micrograms. gonadotropin-releasing hormone antagonist (GnRH-antagonist) per day for 15 days prior to being divided into three groups: 1) animals to be examined immediately, 2) animals to continue receiving 62.5 micrograms. GnRH-antagonist per day alone, and 3) animals to continue receiving GnRH-antagonist + a single intratesticular injection of 20 mg. TLM per testis. Unoperated control and sham-operated animals were also studied. Testicular interstitial fluid (TIF) testosterone concentrations, testicular sperm production and fertility were assessed 105 days after initiation of the experiment. Testicular interstitial fluid testosterone concentrations and sperm production were significantly reduced from control values after the initial 15-day GnRH-antagonist treatment (p < .05). After 105 days of GnRH-antagonist treatment, these values were further reduced (p < .05), but the TIF testosterone and sperm production values of GnRH-antagonist treated animals receiving TLM supplementation were not different from those of controls (p < .05). Fertility trials were also performed. Animals which had received GnRH-antagonist alone for 90 days were completely infertile, but animals receiving GnRH-antagonist + TLM for 90 days had fertility values not different from those of control animals (p < .05). Thus, spermatogenesis reduced because of testicular insufficiency was restored to normal, as was fertility, by intratesticular administration of TLM. This technique has possible clinical applications in selected groups of infertile men.

Effects of surgical repair of experimental left varicocele on testicular temperature, spermatogenesis, sperm maturation, endocrine function, and fertility in rabbits

To evaluate the effectiveness of surgical correction of varicocele in restoring the function of the varicocelized testicle, experimental varicoceles were created in 16 male rabbits by partly ligating the left lumbotesticular trunk. Five control rabbits received a sham operation (group A). Two months later, eight of the varicocelized rabbits underwent surgical repair by ligation and cutting of the dilated left testicular vein (group B). The remaining eight varicocelized animals did not receive any additional treatment (group C). Five months after the initial operation, group C animals had a significantly lower sperm concentration, sperm motility, bilateral testicular androgen-binding protein activity, bilateral testicular vein testosterone concentration, bilateral testicular versus intraabdominal temperature difference, and fertility when compared with groups A and B. These findings suggested that the surgical repair of an experimental varicocele in the rabbit can significantly improve the parameters indicating the harmful effects of the varicocele on the testicles.

On the maintenance of male fertility in the absence of native testosterone secretion: site-directed hormonal therapy in the rat

A method of direct percutaneous injection of testosterone (T)-laden microspheres directly into the testis was used in an attempt to achieve the maintenance of normal intratesticular T concentrations, spermatogenesis, and fertility. Rats were divided into three groups: (1) sham operated/injection controls; (2) animals receiving 250 micrograms/d gonadotropin-releasing hormone (GnRH)-antagonist; and (3) animals receiving GnRH-antagonist as in group 1 plus 20 mg T-laden microspheres/testis. Treatment periods were 45 and 90 days. Serum T, testicular interstitial fluid T, testis weights, epididymal weights, daily sperm production (sperm x 10(6)/g/d), cauda sperm motility, and fertility were assessed in all animals. Gonadotropin-releasing hormone antagonist treatment reduced serum and testicular interstitial fluid to below detectable levels at day 45 and to similar levels at day 90. Supplementation with T-laden microspheres maintained testicular interstitial fluid T at concentrations not different from controls without elevation of serum T concentrations. All other values, including fertility were suppressed by GnRH-antagonist treatment and maintained by supplementation with T-laden microspheres.

Kallikrein therapy of infertile men with varicocele and impaired sperm motility

A randomized group of 65 men with oligoasthenozoospermia and left side varicocele was subjected to a controlled study with kallikrein. Kallikrein (600 units orally per day) was given to 38 men for a period of 3 months. The other group of 27 men remained untreated but were followed up during the same period of time. After kallikrein treatment significant improvements in sperm quality could be observed: percentage of motile spermatozoa from 24.47 +/- 9.01 to 35.26 +/- 11.80, percentage of morphologically normal spermatozoa from 58.42 +/- 5.86 to 71.05 +/- 8.12. There was no improvement in sperm parameters in the untreated group of men. The results suggest that kallikrein therapy is useful for those men who refuse an operative or radiologic treatment of their varicocele and also as a primary or associated therapy of patients who underwent ligature or occlusion of spermatic veins.

Leydig cell function in adolescent boys with varicoceles

The incidence of varicoceles in adolescent boys ranges from 5% to 19.5%. We studied five adolescent boys aged 17 to 20 years with visible left-sided varicoceles. All of them had public hair and testicular volumes between 20 to 25 mL and had achieved stage V of pubertal development. Serum gonadotropin response to the intravenous administration of 100 micrograms of gonadotropin-releasing hormone (GnRH) and testosterone response to the administration of 2,000 IU human chorionic gonadotropin (hCG) daily for 3 days before and 3 months after varicocelectomy were measured. Basal levels of both gonadotropins were in the pubertal range, and there was no significant difference between serum levels before and after varicocelectomy. Both gonadotropins, however, showed increased responses to the administration of GnRH (luteinizing hormone [LH]: basal, 12.0 +/- 5.1 mIU/mL; peak, 105.0 +/- 36.0 mIU/mL; follicle-stimulating hormone [FSH]: basal, 11.6 +/- 4.2 mIU/mL, peak, 60.0 +/- 18.0 mIU/ml) that decreased after varicocelectomy (LH: basal, 14.3 +/- 6.0 mIU/mL; peak, 58.6 +/- 12.0 mIU/mL; FSH: basal, 6.8 +/- 4.6 mIU/mL; peak, 38.0 +/- 8.1 mIU/mL). Serum testosterone response to hCG was also significantly improved by varicocelectomy (testosterone peak: before, 780 +/- 210 ng/dL; after, 1850 +/- 170 ng/dL). Testicular biopsy specimens showed no histologic abnormalities and normal spermatogenesis. Endocrine evaluation in adolescent boys with varicoceles could detect an early Leydig cell dysfunction that could be corrected by varicocelectomy.

Factors predicting the outcome of varicocele repair for subfertility: the value of the luteinizing hormone-releasing hormone test

The mechanism by which varicocele caused infertility is not yet clear. Endocrine factors have been suggested to explain impaired spermatogenesis in patients with varicocele. We conducted a prospective study on testosterone and gonadotropin levels and their response to the luteinizing hormone-releasing hormone test to determine the possible role of a hormonal defect in subfertility. Luteinizing hormone-releasing hormone tests were performed on 11 subfertile men with varicocele preoperatively and 3 months postoperatively. The differences in the luteinizing hormone response were statistically significant. The maximal luteinizing hormone levels also were significantly lower in patients whose spermiogram changed postoperatively. No significant changes were noted in testosterone and other gonadotropin levels postoperatively. A prognostic correlation between the change in response of luteinizing hormone to luteinizing hormone-releasing hormone (preoperatively and postoperatively) and improvement in fertility (pregnancy success) was found. We suggest that the luteinizing hormone-releasing hormone test should be considered to estimate the hormonal derangement and also the prognosis of an operation in subfertile men with varicocele.

The impact of spermatic vein ligation on the male factor in in vitro fertilization-embryo transfer and its relation to testosterone levels before and after operation

Criteria for improved semen quality after varicocele operations are not clear, as they do not express sperm fertilization capacity, its most important qualification. Twenty-two couples, 12 with mechanical female infertility (group I) and 10 with normal female fertility (group II), in whom the husband had subfertile semen in the presence of varicocele, and who had failed preoperative in vitro fertilization-embryo transfer (IVF-ET) attempts, were readmitted for the IVF-ET procedure following the repair of varicocele. In group I, a 20% pregnancy rate was achieved after the operation, while no pregnancies occurred before surgery. In group II, four pregnancies (40%) were achieved after operation. Plasma testosterone (T) levels demonstrated a significant increase in 50% of the patients in both groups after surgery, resulting in a concurrent improved fertilization, cleavage, and pregnancy rates.

Biochemical changes in testicular varicocele

The precise mechanism of the hypospermatogenesis associated with varicocele has remained uncertain, although there have been a number of speculations on the etiology of the associated infertility. The altered spermatogenesis has been attributed to the reflux of toxic metabolites from either adrenal or renal origin, disturbed hormone status, spermatic venous hypertension, testicular hypoxia secondary to stasis, and abnormal temperature regulation. However, the biochemical changes of the testicular tissue with varicocele have been only partially explored. This overview includes the available information on the biochemical change in the testes associated with varicocele as well as the introduction of basic biochemical aspects on the testes, which may give new insights into the possible pathophysiological mechanism of male infertility.

The endocrinology of varicoceles

There is good evidence of an associated abnormality in testicular hormone production and spermatogenesis in some men with varicoceles. This abnormality can be demonstrated with dynamic tests of the hypothalamic-pituitary-testicular axis and by measuring seminal plasma androgen levels. A high proportion of oligozoospermic men who have abnormal hormone profiles will respond favorably to correction of their varicosities. Several oligozoospermic men with varicoceles have normal hormonal profiles. To date, in our unit, none of these men has had an improvement in seminal characteristics after varicocelectomy. This result would suggest that these men have incidental varicoceles. It is not clear what the testicular defect is leading to abnormal spermatogenesis in these men. Clearly, more studies are required in this group of men and in the men with sperm densities greater than 30 X 10(6)/ml, the majority of whom have normal responses to GnRH infusion. More information is needed regarding the intratesticular control of hormone production and spermatogenesis. As our knowledge of the paracrine system within the testis increases, so should our understanding of the mechanisms involved in the association of varicoceles and infertility.

Decrease of topoisomerase I activity in the testes of infertile men with varicocele

Topoisomerase I, which is involved in DNA metabolism, was measured in the testes of 37 infertile men with varicocele, using a minute amount of testicular biopsy specimen. In 38% of infertile men topoisomerase I activity was lower than that of normal men. Forty-six percent of patients with high grade varicocele (grade III) showed reduced topoisomerase I activity, while only 26% of patients with low grade varicocele (grades I and II) showed reduced levels of topoisomerase I. Johnsen's score of the patients with low topoisomerase I activity was lower than that of patients with normal levels of topoisomerase I. The decrease of topoisomerase I activity may be correlated with at least some fraction of hypospermatogenesis associated with varicocele.

The effects of unilateral, experimental varicocele are not mediated through the ipsilateral testis

Unilateral varicocele has been associated with diminished male fertility in humans and with bilateral physiologic and histologic changes in the testis of humans and laboratory animals. In particular, left varicocele in Sprague-Dawley rats results in bilateral increases in testicular temperature and blood flow. The mechanism by which unilateral varicocele can cause testicular changes is not known. The purpose of the present study was to determine whether or not the presence of either the ipsilateral or contralateral testicle is necessary for these effects of the varicocele to occur in the opposite testis. Varicoceles were created in adult, male rats by partial constriction of the left renal vein. Bilateral testicular blood flow was measured by a radiolabelled microsphere distribution technique and testicular temperature was taken with a needle probe thermometer. Right or left orchiectomies were performed on selected animals at the time of surgery to establish the unilateral left varicocele. Animals were studied 30 days after surgery. Mean testicular blood flow was significantly increased (P less than 0.01) in all animals having a left varicocele when compared with animals not having a varicocele regardless of whether a unilateral orchiectomy was performed. Likewise, the mean difference between intraabdominal temperature and intratesticular temperature (delta T) was significantly decreased in all groups of animals having varicoceles when compared with groups without varicoceles whether or not an orchiectomy had been performed. Thus, the studied bilateral effects of left-sided, experimental varicocele in the rat are not dependent upon the presence of a left testicle.

Zinc sulfate therapy for infertile male with or without varicocelectomy

One hundred one men were treated for infertility with 440 mg of zinc sulfate daily for sixty days to two years. All subjects demonstrated low seminal plasma zinc concentrations prior to treatment. Patients were divided into two groups: group [Zn], 65 subjects who underwent zinc therapy alone and group [Var/Zn], 36 subjects who received zinc sulfate therapy after varicocelectomy. In both groups seminal zinc levels were significantly higher (P less than 0.05 and P less than 0.01, respectively) two months after the initiation of zinc therapy. There were no significant changes in sperm count or motility for the [Zn] patients. However, group [Var/Zn] showed a significant increase (P less than 0.05) of sperm motility at two months and twelve months after starting zinc sulfate therapy. We separated the [Var/Zn] patients into two sub-divisions: those who impregnated their wives after therapy, and those who remained infertile despite treatment. Only those patients who impregnated their wives showed a significant (P less than 0.05) increase in sperm motility two months after the initiation of zinc therapy. Those patients of the [Var/Zn] group who remained infertile despite treatment showed a significant increase (P less than 0.05) in sperm motility after twelve months of therapy. Of the [Zn] patients 27.7 per cent (18) successfully impregnated their wives, while the [Var/Zn] patients exhibited a pregnancy rate of 50 per cent (18 patients). These data indicate that zinc sulfate therapy for patients with low seminal zinc concentrations may be an effective treatment for infertile patients especially after varicocelectomy.

Influence of temperature on the function of Sertoli and Leydig cells of human testes

The influence of temperature on Leydig and Sertoli cell functions was investigated in two experiments. One experiment was performed with testes of men with or without varicocele, because the temperature differs between right and left testes of men with left varicocele and right testes of men without varicocele. There were no significant differences in follicle-stimulating hormone (FSH), human chorionic gonadotropin (hCG) receptors, and testosterone (T) concentrations among the testes. The other experiment was performed with the use of testicular organ culture. Specific binding sites for FSH, hCG, and T production were similar in cultured testes maintained at 33 degrees and 37 degrees C for 7 days. It is concluded that high temperature may not disturb Leydig and Sertoli cell functions in the short term.

Hormonal and seminal parameters in infertile men

500 infertile patients (250 with and 250 without left side varicocele) and 33 fertile men were evaluated as far as seminal parameters and the hormonal status were concerned. Sperm motility was constantly lower in infertile patients also when infertile group was compared to fertile one with the same sperm density. Serum testosterone levels were lower in infertile groups when compared to fertile men, and this confirms the existence of an androgenic deficit as a common finding in infertility associated or not to varicocele. FSH and LH increased (p less than 0.001) when sperm density dropped to less than 5 X 10(6) spermatozoa/ml. A negative correlation was found between both gonadotropins and sperm count (p less than 0.001), also after exclusion of azoo- and oligozoospermic (less than 5 X 10(6) spermatozoa/ml) patients (p less than 0.01). Gonadotropins were moreover tightly correlated between each other (p less than 0.001). Our data suggest that both gonadotropins are tightly tuned with sperm output and thus with the spermatogenic potential.

Repair of experimental varicoceles in the rat. Long-term effects on testicular blood flow and temperature and cauda epididymidal sperm concentration and motility

The effects of varicocele and varicocele repair on testicular blood flow, temperature, sperm counts, and sperm motility were assessed in adult male rats. The duration of the experimental varicocele and the varicocele repair were three and two times as long, respectively, as that studied previously. Varicoceles were created by partial ligation of the left renal vein and repairs were accomplished by high ligation of the left spermatic vein. Testicular blood flow was determined by using the radiolabeled microsphere technique. Testicular temperature was taken via needle probe thermometer. Sperm samples were obtained by micropuncture of the cauda epididymidis, and were counted on a hemacytometer and observed for motility under the light microscope. Varicoceles were studied 100 days after their creation. Repairs were performed on varicoceles that had lasted 100 days and the animals were studied 60 days after repair. Mean testicular blood flow (ml/100 g tissue/min) was significantly increased (P less than 0.05) in animals with varicocele (left testis (LT) = 42.2 +/- 1.1, right testis (RT) = 39.1 +/- 1.2) when compared with normal controls (LT = 29.3 +/- 1.6, RT = 29.6 +/- 1.7), animals with varicocele repair (LT = 30.7 +/- 1.3, RT = 30.0 +/- 1.6), or sham-operated animals (LT = 29.7 +/- 1.4, RT = 31.1 +/- 1.4).(ABSTRACT TRUNCATED AT 250 WORDS)

Intratesticular unconjugated steroids in elderly men

As an extension of our studies on the influence of age on testicular function and with the aim of detecting whether the decline in testosterone production by aged testes is accompanied by a block in the biosynthetic chain leading from cholesterol to testosterone, we determined in the testis of young and elderly men, who died suddenly either from a cardiac incident or from accident, intratesticular steroids: pregnenolone, 17 hydroxypregnenolone (3 beta, 17 alpha-dihydroxy-5-pregnen-20-one), dehydroepiandrosterone, androstenediol, (5-androsten-3 beta, 17 beta-diol), progesterone, 17 hydroxyprogesterone, androstenedione, 17 beta-estradiol as well as testosterone, dihydrotestosterone (5 alpha-androstan-17 beta-ol-3-one) and androstanediol (5 alpha androstane-3 alpha, 17 beta-diol). The intratesticular steroid pattern in elderly men was essentially characterized by a decrease of the 5-ene steroid concentration, whereas we did not observe a decrease in the 4-ene steroids, progesterone concentration being even significantly higher in the aged testes. There was no evidence for a decrease in either lyase or 17-hydroxylase activity. It is suggested that the steroid pattern as observed in the aged testes is the consequence of a decreased oxygen supply, due to a decreased testicular perfusion.

Paracrine control of the testis

The mammalian testis is under the overall control of pituitary gonadotropins but the utilization of these signals to achieve normal testicular function involves complex local interactions between the Sertoli and germ cells, the Sertoli and peritubular cells, and the Sertoli and Leydig cells as well as local control of the testicular vasculature. These interactions serve two purposes: (1) to coordinate the functions of the three testicular compartments (seminiferous tubules, interstitium and the vasculature); and (2) to control the complex but orderly sequence of events that constitutes the spermatogenic cycle. This process, which involves multiplication, differentiation and translocation of the germ cells is organized into a sequence of stages, each of which is composed of a constant association of germ cells at four or five different stages of development. At each stage of the spermatogenic cycle, different events occur and the function of the Sertoli cells alters, probably in accordance with the changing requirements of the associated germ cells. As yet, our understanding of these many local events is extremely limited, particularly with respect to the identity of the hormones/factors involved in controlling the various processes. Our knowledge of paracrine control mechanisms in the testis is derived mainly from studies of the rat, but as the process of spermatogenesis is essentially the same in most mammals and involves the same sequence of events, then findings in the rat can probably be applied in general, if not in detail, to the human testis; the limited direct information available on the human testis supports this view. As most cases of infertility in men occur despite normal or raised serum gonadotropin levels and are characterized by the production of reduced or normal numbers of sperm, then it seems likely that malfunction of one or more of the intricate paracrine processes within the testis may be involved in the aetiology of idiopathic oligospermia. It is therefore argued that advances in our knowledge of the paracrine control of the testis should have major repercussions on our ability to understand, and eventually treat, idiopathic infertility in men, and also to induce infertility for contraceptive purposes.

Seminal plasma hormone profile in infertile men with and without varicocele

Seminal plasma FSH, LH, prolactin, testosterone, and oestradiol were estimated in 41 infertile men with varicocele and 45 infertile men without varicocele who failed to impregnate their wives after 2 years of marriage and 30 fertile men. There was significant elevation of FSH in the seminal plasma of the infertile men with varicocele compared with the seminal plasma of the other infertile and fertile men. Seminal LH and prolactin values were similar in both infertile groups but significantly higher than in the fertile men. Testosterone and oestradiol levels in the seminal plasma of infertile men with varicocele were lower than in the fertile and the other infertile males. Finding that both steroids were decreased in infertile men with varicocele could explain disturbed function of spermatozoa in men with varicocele. Further analysis will elucidate the importance of these hormone findings in the seminal plasma of infertile men with varicocele.

The causes of male infertility in 504 consecutive Nigerian patients

The causes of infertility in 504 men were studied prospectively. The major causes were varicocele (28.8%), infection (20.8%), bilateral testicular failure (15%), idiopathic oligospermia (6.6%), multifactorial (5.6%), cryptorchidism (4%), sexual problems (3.8%) and surgical injury (1.6%). Unilateral testicular torsion and sickle cell disease though of less frequent occurrence were of particular interest because their roles are only now beginning to be realized. Gonadotrophin deficiency was an insignificant cause of subfertility. In spite of the high incidence of infection and past history of urethritis Neisseria gonorrheae was surprisingly not isolated from any patient. Compared with Caucasian studies, the high incidence of infection, and the low incidence of gonadotrophin deficiency are major points of difference.

Effects of varicocele after unilateral orchiectomy and sympathectomy

An experimental varicocele was created in the adult rat by partial ligation of the left renal vein. There was a significant bilateral elevation of both testicular blood flow and temperature in the varicocele animals (p less than 0.01). Mean testicular blood flow for control and varicocele animals was 29.6 +/- 1.0 and 39.8 +/- 2.0 ml./min./100 gm. tissue, while mean testicular temperature was 34.4 +/- 0.1 and 35.3 +/- 0.2C, respectively. A left orchiectomy was combined with a left varicocele to determine if the left testis is essential for the right testicular response to a varicocele. Elevation of right testicular blood flow was not altered by left orchiectomy (p less than 0.05); however, right testicular temperature was no longer significantly increased. Mean right testicular blood flow and temperature for this group was 39.0 +/- 1.5 ml./min./100 gm. tissue and 34.2 +/- 0.15C, respectively. A left sympathectomy was combined with a left varicocele to ascertain if the right testicular response to the left varicocele was mediated through a neural pathway. A significant bilateral increase in testicular blood flow was noted with a left sympathectomy alone, and thereby masked the ability to evaluate the right testicular response to the simultaneous left sympathectomy and varicocele. Elevation of right testicular blood flow in response to the left varicocele is independent of the presence of a left testis and any immune response it may stimulate. The role of the sympathetic nervous system as a mediator of the bilateral varicocele effect remains undetermined.

Testosterone, FSH and LH in human spermatic and cubital venous plasma in varicocele patients

The plasma level of testosterone, FSH and LH were determined simultaneously in spermatic and cubital veins in 12 patients with varicocele. The testosterone levels in spermatic veins were 13.4 +/- 5.3 times higher than in cubital veins. FSH and LH levels were higher in cubital than in spermatic vein. No correlation was found between the number of spermatozoa in 1 ml of semen, and the level of the three hormones studied, either in the cubital or in spermatic vein.

Stagnation of blood in the microcirculatory vessels in the testes of men with varicocele

This study reports on the stagnation of blood within the microcirculatory vessels of the testes of patients with varicocele. Both fine structural and quantitative studies were carried out on testicular biopsies from 14 men with varicocele and a control group of three men. Arterioles, capillaries, and venules were completely filled with blood in all affected testes. Enlarged pores were also noticed between the endothelial cells of these affected vessels. Lumen diameters of the arterioles were significantly decreased in the affected testis compared to controls. No change in the overall diameter of the arterioles and venules was noted. Significant thickening of the limiting membrane was also noted in the affected testis. It was concluded that the stagnation of blood in the microcirculatory vessels may cause local hypoxia and ischemia, which lead to spermatogenic disorders.

Further studies on testicular lipids and glycogen in human patients with unilateral varicocele

In the present study the lipid and glycogen content of human testis in patients with unilateral varicocele is presented. Eight cases were taken for the present study. Testicular biopsy specimens taken from these patients were analyzed and the normal testis acted as control groups. There was marked increase in total lipids, ester cholesterol and glycerides in the testis of varicocele patients. The abnormal increase observed in estercholesterol may be due to non-utilization of cholesterol esters for androgen biosynthesis. The glycogen level was reduced significantly in the affected testis. Thus, varicocele seem to alter the availability of substrates of energy required for normal functioning of germinal and non-germinal cells which results in defective spermatogenesis and steroidogenesis.

Physiopathologic aspects of Leydig cell function in varicocele patients

Leydig cell function was studied in 108 varicocele (V) patients with a mean age of 30.9 years, and a control group (C) of 46 men with a mean age of 30 years. Plasma gonadotropin levels were determined before and after GNRH stimulation. Testosterone (T), 17-OH-progesterone (17-OH-P), dihydrotestosterone (DHT) and estradiol (E2) were also assayed. Mean plasma T levels were significantly decreased in varicocele patients (V = 416 +/- 12.9, n = 106; C = 487 +/- 19.9, n = 40; P less than 0.01), while the basal 17-OH-P/T ratio was significantly increased (V = 0.38 +/- 0.02, n = 56; C = 0.28 +/- 0.02, n = 40; 0.02 greater than P greater than 0.01) and remained higher after hCG stimulation (P less than 0.01). No significant differences in mean sex steroid levels were observed when comparing varicocele patients with normal sperm counts (VN) and those who had oligozoospermia (VO). There was a significant negative linear correlation between age and 17-OH-P (n = 56; r = -0.47; P less than 0.01) and T values (n = 106; r = 0.27; P less than 0.01) in varicocele patients, which contrasted with the absence of any significant correlation with age in the controls. These data suggest that the duration of idiopathic varicocele influences testicular hormone secretion.

The influence of age on Leydig cell function in patients with varicocele

In a large group of patients with varicocele (n = 108, mean age: 30.9 years) Leydig cell function was investigated by determining the plasma levels of gonadotrophins under basal conditions and after GnRH stimulation, and by measuring the plasma levels of 17-OH-progesterone (17-OH-P), testosterone (T), dihydrotestosterone (DHT) and oestradiol (E2). There was a significant positive correlation between age and the peak plasma LH values after GnRH stimulation (n = 48, r = 41, P less than 0.01). Conversely, an inverse correlation was observed between age and the basal plasma levels of 17-OH-P (n = 56, r = 0.47, P less than 0.01) and T (n = 108, r = 0.27, P less than 0.01). In normals controls of the same age range (n = 46, mean age: 30 years) such correlations were absent. In patients with varicocele, the 17-OH-P/T ratio was increased significantly in peripheral plasma under basal conditions (P less than 0.01) and after hCG stimulation (P less than 0.05), and a similar increase was found in spermatic venous blood. This suggests that in varicocele patients there is some enzymatic impairment involving the last steps of T biosynthesis. In order to verify the influence of ologozoospermia on plasma steroid levels we divided the patients into 2 groups according to sperm count (more than or less than 10 X 10(6)/ml). Three analyses of variance were then carried out between these 2 groups of patients: 1) analysis of peripheral plasma T levels; 2) analysis of peripheral plasma levels of 17-OH-P and 3) spermatic vein levels of these 2 steroids. However, none of these analyses revealed any significant difference between the 2 groups of patients. When we re-grouped the patients according to age (15-30 and 30-45 years) the same analyses of variance revealed significant differences. These results therefore suggest that the duration of idiopathic varicocele per se influences Leydig cell activity.