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Updated: Jul 11, 2026

Remote Neuronal Activation Coupled with Automated Blood Sampling to Induce and Measure Circulating Luteinizing Hormone in Mice
Published on: August 25, 2023
[Change of pulsatile release and luteinizing hormone response to naloxone related to testicle damage]
Carlos A Villanueva Díaz1, Rubén Pineda Viedas, Mirna Guadalupe Echavarría Sánchez
1Clínica de Andrología, Instituto Nacional de Parinatología, DF México. villanuevacmx@yahoo.com.mx
Objective:
To compare the pulsatile release of LH, the tone of endogenous opioids and the mass of LH secreted after a naloxone infusion in healthy subjects and patients with normogonadotropic oligospermia (NO) in a model of progressive testicular damage.
Patients And Methods:
Pulsatile secretion of LH was analyzed in a period of 8 hours in a group of healthy subjects (group 3, n=5), in patients with NO and FSH/LH ratio <1.6 (group 1, n=5) and in patients with NO and FSH/LH ratio >1.6 (group 2, n=5). The area under the curve of LH response after naloxone infusion was also calculated.
Results:
Free serum testosterone concentration was lower (p < 0.01) and estradiol concentration higher in patients with NO than control subjects (1 vs. 3: p = 0.01; 2 vs. 3: p = 0.001). Frequency of pulses in group 1 was 3.33 +/- 0.57/8 h, in group 2: 4 +/- 1/8 h; and in group 3: 2.66 - 0.57/8 h (2 vs. 3 p < 0.01; 2 vs. 1 p = 0.05). The area under the curve after naloxone infusion was 19,300.44 +/- 11,403.31 in group 1, 5696.09 +/- 1753.44 in group 2; and 3080.97 +/- 1159.78 in group 3 (1 vs. 3 Anova p = 0.01).
Conclusions:
The data indicate that patients with NO have a subclinical pantesticular failure and that the opioid tone is increased at the initial phase of testicular dysfunction, but it decreases at more advanced stages of testicular damage.
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