Investigation of the Pharmacokinetics of Diazepam in Juvenile Channel Catfish (Ictalurus Punctatus)

PDF Version Also Available for Download.

Description

The presence of pharmaceuticals in the environment is becoming an increasing regulatory and scientific concern. Thus, the metabolic profile and bioconcentration potential of diazepam, a model benzodiazepine, were examined, as well as effects on the endocrine system in channel catfish. Through the use of specific and non-specific cytochrome P450 (CYP450) inhibitors, it was determined that CYP3A-like enzymes may play a role in the biotransformation of diazepam into temazepam; however, the isoform(s) required for the formation of other metabolites is still unknown. Overall, only around 7-8% of diazepam is biotransformed into two known metabolites. Due to the lack of inherent metabolism ... continued below

Creation Information

Overturf, Carmen L. December 2013.

Context

This dissertation is part of the collection entitled: UNT Theses and Dissertations and was provided by UNT Libraries to Digital Library, a digital repository hosted by the UNT Libraries. It has been viewed 276 times , with 4 in the last month . More information about this dissertation can be viewed below.

Who

People and organizations associated with either the creation of this dissertation or its content.

Publisher

Rights Holder

For guidance see Citations, Rights, Re-Use.

  • Overturf, Carmen L.

Provided By

UNT Libraries

With locations on the Denton campus of the University of North Texas and one in Dallas, UNT Libraries serves the school and the community by providing access to physical and online collections; The Portal to Texas History and UNT Digital Libraries; academic research, and much, much more.

Contact Us

What

Descriptive information to help identify this dissertation. Follow the links below to find similar items on the Digital Library.

Degree Information

Description

The presence of pharmaceuticals in the environment is becoming an increasing regulatory and scientific concern. Thus, the metabolic profile and bioconcentration potential of diazepam, a model benzodiazepine, were examined, as well as effects on the endocrine system in channel catfish. Through the use of specific and non-specific cytochrome P450 (CYP450) inhibitors, it was determined that CYP3A-like enzymes may play a role in the biotransformation of diazepam into temazepam; however, the isoform(s) required for the formation of other metabolites is still unknown. Overall, only around 7-8% of diazepam is biotransformed into two known metabolites. Due to the lack of inherent metabolism of diazepam in channel catfish, further analysis was conducted to determine the tissue-specific bioconcentration potential of diazepam in catfish. Various tissues were analyzed for the presence of diazepam as well as metabolites and bioconcentration factors (BCF) were calculated, which were all well below regulatory threshold values (> 2000). Additionally, modulation of the endocrine system by diazepam was examined by measuring steroid hormone concentrations and analyzing mRNA expression of selected steroidogenic enzymes and receptors. Two steroidogenic enzymes were modulated following diazepam exposure, indicating potential endocrine disrupting properties of diazepam. Together, these data suggest that diazepam exhibits low metabolic transformation rates in channel catfish, which may lead to accumulation of benzodiazepine compounds that may negatively affect the endocrine system. However, further studies should be aimed at identifying other steroidogenic enzymes and/or receptors that may be modulated following diazepam exposure.

Language

Collections

This dissertation is part of the following collection of related materials.

UNT Theses and Dissertations

Theses and dissertations represent a wealth of scholarly and artistic content created by masters and doctoral students in the degree-seeking process. Some ETDs in this collection are restricted to use by the UNT community.

What responsibilities do I have when using this dissertation?

When

Dates and time periods associated with this dissertation.

Creation Date

  • December 2013

Added to The UNT Digital Library

  • Nov. 8, 2014, 11:56 a.m.

Description Last Updated

  • June 27, 2017, 11:19 a.m.

Usage Statistics

When was this dissertation last used?

Yesterday: 0
Past 30 days: 4
Total Uses: 276

Interact With This Dissertation

Here are some suggestions for what to do next.

Start Reading

PDF Version Also Available for Download.

International Image Interoperability Framework

IIF Logo

We support the IIIF Presentation API

Overturf, Carmen L. Investigation of the Pharmacokinetics of Diazepam in Juvenile Channel Catfish (Ictalurus Punctatus), dissertation, December 2013; Denton, Texas. (digital.library.unt.edu/ark:/67531/metadc407799/: accessed July 21, 2018), University of North Texas Libraries, Digital Library, digital.library.unt.edu; .