Dataset Information

Bladder Dysfunction in an Obese Zucker Rat: The Role of TRPA1 Channels, Oxidative Stress, and Hydrogen Sulfide.

ABSTRACT:

Purpose

This study investigates whether functionality and/or expression changes of transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1) channels, oxidative stress, and hydrogen sulfide (H₂S) are involved in the bladder dysfunction from an insulin-resistant obese Zucker rat (OZR).

Materials and methods

Detrusor smooth muscle (DSM) samples from the OZR and their respective controls, a lean Zucker rat (LZR), were processed for immunohistochemistry for studying the expression of TRPA1 and TRPV1 and the H₂S synthase cystathionine beta-synthase (CBS) and cysthathionine-?-lyase (CSE). Isometric force recordings to assess the effects of TRPA1 agonists and antagonists on DSM contractility and measurement of oxidative stress and H₂S production were also performed.

Results

Neuronal TRPA1 expression was increased in the OZR bladder. Electrical field stimulation- (EFS-) elicited contraction was reduced in the OZR bladder. In both LZR and OZR, TRPA1 activation failed to modify DSM basal tension but enhanced EFS contraction; this response is inhibited by the TRPA1 blockade. In the OZR bladder, reactive oxygen species, malondialdehyde, and protein carbonyl contents were increased and antioxidant enzyme activities (superoxide dismutase, catalase, GR, and GPx) were diminished. CSE expression and CSE-generated H₂S production were also reduced in the OZR. Both TRPV1 and CBS expressions were not changed in the OZR.

Conclusions

These results suggest that an increased expression and functionality of TRPA1, an augmented oxidative stress, and a downregulation of the CSE/H₂S pathway are involved in the impairment of nerve-evoked DSM contraction from the OZR.

SUBMITTER: Blaha I

PROVIDER: S-EPMC6721245 | biostudies-literature | 2019

REPOSITORIES: biostudies-literature

ACCESS DATA

Publications

Bladder Dysfunction in an Obese Zucker Rat: The Role of TRPA1 Channels, Oxidative Stress, and Hydrogen Sulfide.

Blaha Igor I López-Oliva María Elvira ME Martínez María Pilar MP Recio Paz P Agis-Torres Ángel Á Martínez Ana Cristina AC Benedito Sara S García-Sacristán Albino A Prieto Dolores D Fernandes Vítor S VS Hernández Medardo M

Oxidative medicine and cellular longevity 20190820

<h4>Purpose</h4>This study investigates whether functionality and/or expression changes of transient receptor potential vanilloid 1 (TRPV1) and transient receptor potential ankyrin 1 (TRPA1) channels, oxidative stress, and hydrogen sulfide (H<sub>2</sub>S) are involved in the bladder dysfunction from an insulin-resistant obese Zucker rat (OZR).<h4>Materials and methods</h4>Detrusor smooth muscle (DSM) samples from the OZR and their respective controls, a lean Zucker rat (LZR), were processed for ...[more]

PMID: 31531184

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Dataset Information

Bladder Dysfunction in an Obese Zucker Rat: The Role of TRPA1 Channels, Oxidative Stress, and Hydrogen Sulfide.

Purpose

Materials and methods

Results

Conclusions

Publications

Bladder Dysfunction in an Obese Zucker Rat: The Role of TRPA1 Channels, Oxidative Stress, and Hydrogen Sulfide.

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