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Updated: Jul 14, 2026
05:48
An In Vivo Method to Study Mouse Blood-Testis Barrier Integrity
Published on: December 2, 2018
Drugs and the blood-testis barrier
Environmental Health Perspectives
|June 1, 1978
Summary
The blood-testis barrier controls substance entry into seminiferous tubules. Dimethylnitrosamine (DMNA) rapidly enters tubules, possibly after conversion from a precursor, concentrating toxins within.
Area of Science:
- Reproductive biology
- Toxicology
- Cellular physiology
Background:
- The blood-testis barrier (BTB) is crucial for maintaining the testicular microenvironment.
- Understanding how substances cross the BTB is vital for assessing testicular toxicity.
- Simple and facilitated diffusion are known mechanisms for substance transport across the BTB.
Purpose of the Study:
- To discuss evidence for the functional and morphological aspects of the blood-testis barrier.
- To examine the transport mechanisms of substances entering the seminiferous tubule.
- To investigate the differential entry rates of methylmethanesulfonate (MMS) and dimethylnitrosamine (DMNA) into the seminiferous tubules.
Main Methods:
- Review of functional and morphological evidence for the blood-testis barrier.
- Analysis of data on the entry of MMS and DMNA into seminiferous tubules.
- Comparison of observed entry rates with expected rates based on testicular DNA methylation.
Main Results:
- Both MMS and DMNA rapidly enter the seminiferous tubules.
- The rapid entry of DMNA contradicts expectations based on testicular DNA methylation rates.
- DMNA in blood appears to be gradually converted into a nonpermeant compound.
Conclusions:
- The blood-testis barrier permits rapid entry of both MMS and DMNA.
- DMNA's transport kinetics suggest a metabolic conversion in the blood prior to or during entry.
- A hypothesis is proposed for a precursor-mediated concentration of toxic substances within the tubules.
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