Long-Term Aspirin Administration Has No Effect on Erectile Function: Evidence from Adult Rats and Ageing Rat Model

Abstract

As the broad spectrum pharmacological action, aspirin has been one of the most widely used medicines since its initial synthesis; however, the association between aspirin and erectile function is still controversial. We aim to explore whether long-term aspirin administration deteriorates or preserves erectile function from adult rats and ageing rat model. Twenty adult rats (10 weeks of age) and twenty ageing rats (80 weeks of age) were randomly divided into four groups as follows: Adult-Control (normal saline [NS]), Adult-Aspirin (aspirin, 10 mg/kg/d), Ageing-Control (NS), and Ageing-Aspirin (aspirin, 10 mg/kg/d) groups (n = 10 per group). For all rats, erectile function was assessed by maximum intracavernous pressure (ICP), total area under ICP curve (AUC), ICP/mean arterial pressure (MAP) ratio, and MAP. The total treatment duration was one month. Protein expression levels of cyclooxygenase-1 (COX-1), COX-2, endothelial nitric oxide synthase (eNOS), and nNOS of the corpus cavernosum were detected by Western blot. ELISA kits were used to determine 6-keto PGF 1a , PGE 2 , TXB 2 , cyclic adenosine monophosphate (cAMP), and cyclic guanosine monophosphate (cGMP) levels. Total nitric oxide (NO) concentration was measured using a fluorometric assay kit. As a result, Ageing-Control rats revealed significantly decreased ICP, AUC, and ICP/MAP ratios compared to Adult-Control rats, and these effects were accompanied by reduced eNOS protein expression and lower total NO and cGMP levels; however, no difference was found in nNOS protein expression. For adult rat groups, aspirin significantly inhibited the production of 6-keto PGF 1a , PGE 2 , and TXB 2 ; however, it neither changed the ICP, AUC, or ICP/ MAP ratios nor altered the protein expression of eNOS, nNOS, COX-1, and COX-2. Meanwhile, aspirin did not influence the concentrations of total NO, cAMP, or cGMP. The same tendency was also found in the ageing rat model, which confirmed that aspirin did not alter erectile function. Our data suggested that long-term aspirin administration did not strengthen or weaken erectile function in adult rats or ageing rat model. Thus, it had no impact on erectile function.

Characteristics of penile growth in pubertal rats and a non‐invasive method to lengthen the penis

“…With a 1-week washout period after penile length measurement, erectile function was evaluated as previously described. 15 Briefly, after anesthesia induction, the isoflurane concentration was decreased and maintained at 2%. The carotid was exposed and can-…”

“…The proximal penis stored with liquid nitrogen was homogenized, separated by SDS-PAGE, and transferred to a polyvinylidene difluoride membrane using standard procedures. 2,15 Primary antibody of LOX (1:1000, Abcam) was selected and normalized using glyceraldehyde-3-phosphate dehydrogenase (GAPDH; 1:200, Zen BioScience Co., Ltd.). Data were collected using the Bio-Rad ChemiDoc MP (Bio-Rad), and the band intensities were quantified using ImageJ software (National Institute of Health).…”

“…With a 1-week washout period after penile length measurement, erectile function was evaluated as previously described. 15 Briefly, after anesthesia induction, the isoflurane concentration was decreased and maintained at 2%. The carotid was exposed and cannulated with heparinized (200 IU/mL) venipuncture (26 G; Closed IV Catheter System, Becton Dickinson Medical Devices Co. Ltd.) connected to a BL420 bio-function experiment system (Chengdu TME Technology Co. Ltd.) to record the arterial pressure.…”

Efficacy of Aspirin for Vasculogenic Erectile Dysfunction in Men: A Meta-Analysis of Randomized Control Trials

“…Although this meta-analysis shows strong evidence that using aspirin may significantly improve erectile function, there have been a few animal-based and human population-based and hospital-based studies that have suggested that aspirin may have no effect on or may increase the odds of ED (Kupelian et al, 2013;Li et al, 2019;Patel et al, 2016;Shiri et al, 2006). There were only two RCTs available for the meta-analysis.…”

Potential Effect of the Circadian Clock on Erectile Dysfunction

“…Actually, old rats with ED always have a lower amount of NOS-containing nerves, as well as decreased NOS mRNA expression and NOS activity [ 40 , 58 ]. Our previous study also showed that aging rats had lower intracavernous pressure (ICP) and eNOS expression in the corpus cavernosum [ 59 ]. Additionally, rats with diabetes or bilateral cavernous nerve crush (BCNC) induced ED showed lower nNOS or eNOS expression and activity, as well as impaired NO production in the corpus cavernosum [ 39 , 40 , 60 , 61 ].…”