Related Experiment Video
Updated: Mar 8, 2026
Establishment of Rat Models Mimicking Gender-affirming Hormone Therapies
Published on: January 10, 2025
Impact of Testosterone on Endothelial Function Varies by GnRH Agonist Treatment
Natalie J Nokoff1, Lyndsey DuBose2, Samantha Bothwell1
1Division of Endocrinology, Department of Pediatrics, University of Colorado Anschutz Medical Campus, Aurora, CO 80045, USA.
Context:
Transgender adults taking testosterone have impaired endothelial function, a triggering mechanism for cardiovascular disease. The impact of testosterone with and without gonadotropin-releasing hormone agonists (GnRHa) on endothelial function in transgender adolescents is unknown.
Objective:
To evaluate the effects of 12 months of testosterone therapy on endothelial function among transgender adolescents and whether the effects differ based on exposure to GnRHa.
Design:
Longitudinal, observational study with assessments prior to and after 1 and 12 months of testosterone therapy.
Setting:
Academic regional referral center.
Participants:
Nineteen adolescents with a female sex (8 receiving GnRHa, 11 not receiving GnRHa).
Interventions:
Clinically prescribed testosterone.
Main Outcome Measures:
Endothelial function assessed by brachial artery flow mediated dilation (FMD) at baseline and after 1 and 12 months testosterone therapy. Differences between groups were assessed at baseline by t-test and over time with a linear regression model with a time*group interaction.
Results:
FMD was lower in GnRHa + compared to GnRHa- individuals at baseline (7.9 ± 2.5% vs 10.9 ± 2.9%, P = .029) and after 1 month (P = .042) of testosterone therapy. After 12 months of testosterone, FMD was similar between groups: 9.9 ± 4.2% for GnRHa + and 9.8 ± 2.8% for GnRHa- (P = .965). There was a significant interaction in the linear regression model for FMD (P = .030) with an increase in FMD for GnRHa + individuals and a decrease in FMD for GnRHa- individuals after 12 months of testosterone.
Conclusion:
Prior to testosterone therapy, GnRHa + individuals had lower endothelial function compared to GnRHa- individuals. The effects of testosterone on endothelial function were modulated by GnRHa status.
Related Concept Videos
01:18Treatment for Pulmonary Arterial Hypertension: Endothelin Receptor Antagonists
ETs are synthesized through a complex sequence of enzymatic steps, primarily involving an enzyme referred to as endothelin-converting enzyme...
01:16Antianginal Drugs: Nitrates and β-Blockers
Organic nitrates, such as nitroglycerin, play a pivotal role. Once metabolized, they liberate nitric oxide, a molecular marvel. Nitric oxide triggers guanylyl cyclase and augments cGMP production. This biochemical cascade orchestrates the relaxation of vascular smooth muscles, ushering in vasodilation and enhancing coronary blood flow....
01:28Nitric Oxide Signaling Pathway
01:23Antihypertensive Drugs: Vasodilators
01:23Treatment for Pulmonary Arterial Hypertension: Prostacyclin Receptor Agonists
These agonists bind to the IPR receptor situated on the plasma membrane of the pulmonary artery smooth muscle cells. This binding triggers a cascade of reactions known as the GS-AC-cAMP-PKA pathway. This pathway results in the relaxation of smooth muscle...
01:28Treatment for Pulmonary Arterial Hypertension: Phosphodiesterase Inhibitors
Among the PDE5 inhibitors, sildenafil (Revatio) stands out as a competitive and selective inhibitor. It operates by elevating cellular levels of cGMP and augmenting signaling through the cGMP-PKG pathway, promoting vasodilation. Upon oral...