Influence of endomorphins along the pituitary-ovary axis in the Mozambique Tilapia Oreochromis mossambicus.

Fish Physiol Biochem

Neuroendocrinology Research Lab, Department of Studies in Zoology, Karnatak University, Dharwad, 580003, India.

Published: February 2020

AI Article Synopsis

  • Endomorphins EM-1 and EM-2 are tetrapeptides that interact with μ-opioid receptors and their effects on fish reproduction, particularly in the Mozambique tilapia, are being studied.
  • The study involved different treatment groups, including controls and those treated with EM-1 or EM-2, revealing that EM-1 treatment increased stage I follicles while both peptides reduced the number of stage V follicles and affected luteinizing hormone cell activity.
  • Results indicate that endomorphins may inhibit ovarian development along the pituitary-ovary axis in fish, marking a new discovery in understanding their reproductive biology.

Article Abstract

Endomorphins (EM-1 and EM-2) are the tetrapeptides involved in pain and neuroendocrine responses with a high affinity for μ-opioid receptors in vertebrates. However, their role in fish reproduction is not clear. The aim of this study was to investigate the influence of EM-1 and EM-2 on the pituitary-ovary axis in the Mozambique tilapia Oreochromis mossambicus. The experimental set-up consisted of four groups, namely, initial controls, controls, EM-1- and EM-2-treated groups (n = 10 in each group consisting of two replicates). Although the number of stage IV (vitellogenic) follicles was significantly lower (P < 0.05) in controls compared to initial controls, the stage V (preovulatory) follicles were present in controls in contrast to their absence in initial controls. Treatment of 40 μg EM-1/0.1 ml saline/fish/day for 22 days resulted in significant increase (P < 0.05) in the number of stage I follicles compared to controls. While similar treatment of EM-2 did not significantly alter the number of stage I follicles compared to controls, the number of stage II follicles was significantly lower (P < 0.05) in this group compared to those of controls and EM-1 treated fish. The number of stage III and IV follicles did not significantly differ among controls, EM-1- and EM-2-treated groups. However, a significant reduction (P < 0.05) in the mean number of stage V follicles was observed in EM-1- and EM-2-treated fish compared to controls. These changes were concomitant with significant reduction (P < 0.05) in the intensity and the percent area of immunoreactivity of luteinizing hormone (LH) secreting cells in the proximal pars distalis (PPD) of the pituitary gland and significantly higher (P < 0.05) percent occurrence of follicular atresia in EM-1- and EM-2-treated fish compared to those of controls. Taken together, these results suggest an inhibitory effect for endomorphins along the pituitary-ovary axis, for the first time in fish.

Download full-text PDF

Source
http://dx.doi.org/10.1007/s10695-019-00731-5DOI Listing

Publication Analysis

Top Keywords

number stage
24
compared controls
20
em-1- em-2-treated
16
stage follicles
16
pituitary-ovary axis
12
controls
12
initial controls
12
endomorphins pituitary-ovary
8
axis mozambique
8
mozambique tilapia
8

Similar Publications

Exosome markers, CD63 and CD81, belong to the tetraspanin family and are expressed in solid tumors. It has been reported that these tetraspanin family members are prognostic factors in some cancers. However, the expression of CD63 and CD81 in pathological breast cancer specimens has not been reported.

View Article and Find Full Text PDF

Research has shown that married individuals live longer lives than unmarried women and men. A smaller number of studies have included non-marital cohabitation and have found that their mortality falls between the married and other unmarried groups. There are indications that the cohabiting population is diverse in terms of mortality risk, yet very little is known about how the association is related to age and stages of the life course.

View Article and Find Full Text PDF

Purposes: This study aimed to clarify the clinical outcomes of Bacillus Calmette-Guérin (BCG) treatment in patients with urothelial carcinoma (UC) of the prostatic urethra.

Methods: Between August 2003 and January 2023, 428 patients with non-muscle-invasive UC received BCG treatment (Tokyo strain, 80 mg, ≥ 5 times) in our hospital; 39 had UC of the prostatic urethra. We evaluated the cumulative incidence of intravesical recurrence, progression (muscle-invasive bladder cancer [MIBC] or metastasis), and subsequent radical cystectomy after BCG treatment in patients with UC of the prostatic urethra.

View Article and Find Full Text PDF

Purpose: Proctectomy is frequently deferred at index colectomy for ulcerative colitis due to acuity or immunosuppressive treatments. The retained rectum remains symptomatic in over 50% with associated cancer risk. Management options include index or delayed proctectomy with or without restoration of continuity or surveillance.

View Article and Find Full Text PDF

Selective breeding is a potent method for developing strains with enhanced traits. This study compared the growth performance and stress responses of the genetically improved Abbassa Nile tilapia strain (G9; GIANT-G9) with a local commercial strain over 12 weeks, followed by exposure to stressors including high ammonia (10 mg TAN/L), elevated temperature (37 °C), and both for three days. The GIANT-G9 showed superior growth, including greater weight gain, final weight, length gain, specific growth rate, and protein efficiency ratio, as well as a lower feed conversion ratio and condition factor compared to the commercial strain.

View Article and Find Full Text PDF

Want AI Summaries of new PubMed Abstracts delivered to your In-box?

Enter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!