Influence of light and temperature on the secretory activity of the harderian gland of the green frog, Rana esculenta

Minucci, Sergio; Baccari, Gabriella Chieffi; Matteo, Loredana Di; Marmorino, C; d’Istria, M.; Chieffi, G.

doi:10.1016/0300-9629(90)90206-8

Cited by 18 publications

(9 citation statements)

References 7 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Excretory lipids also act in thermoregulation of gerbils (Thiessen 1988) and blind mole rats (Shanas & Terkel 1996). HG activity is influenced by both exogenous factors (light and temperature) (Minucci et al 1990, Buzzell et al 1994, Santillo et al 2011a) and endogenous factors (hormones). Androgens seem to be involved in the control of HG secretory activity (d'Istria et al 1991, Chieffi Baccari et al 1993, Santillo et al 2011a, as well sexual dimorphism in the golden hamster gland (McMasters & Hoffman 1984, Coto-Montes et al 2009).…”

Section: Introductionmentioning

confidence: 99%

Triiodothyronine induces lipid oxidation and mitochondrial biogenesis in rat Harderian gland

Santillo

Burrone

Falvo

et al. 2013

Journal of Endocrinology

View full text Add to dashboard Cite

The rat Harderian gland (HG) is an orbital gland producing a copious lipid secretion. Recent studies indicate that its secretory activity is regulated by thyroid hormones. In this study, we found that both isoforms of the thyroid hormone receptor (Tra (Thra) and Trb (Thrb)) are expressed in rat HGs. Although Thra is expressed at a higher level, only Thrb is regulated by triiodothyronine (T 3 ). Because T 3 induces an increase in lipid metabolism in rat HGs, we investigated the effects of an animal's thyroid state on the expression levels of carnitine palmitoyltransferase-1A (Cpt1a) and carnitine palmitoyltransferase-1B (Cpt1b) and acyl-CoA oxidase (Acox1) (rate-limiting enzymes in mitochondrial and peroxisomal fatty acid oxidation respectively), as well as on the mitochondrial compartment, thereby correlating mitochondrial activity and biogenesis with morphological analysis. We found that hypothyroidism decreased the expression of Cpt1b and Acox1 mRNA, whereas the administration of T 3 to hypothyroid rats increased transcript levels. Respiratory parameters and catalase protein levels provided further evidence that T 3 modulates mitochondrial and peroxisomal activities. Furthermore, in hypothyroid rat HGs, the mitochondrial number and their total area decreased with respect to the controls, whereas the average area of the individual mitochondrion did not change. However, the average area of the individual mitochondrion was reduced by w50% in hypothyroid T 3 -treated HGs, and the mitochondrial number and the total area of the mitochondrial compartment increased. The mitochondrial morphometric data correlated well with the molecular results. Indeed, hypothyroid status did not modify the expression of mitochondrial biogenesis genes such as Ppargc1a, Nrf1 and Tfam, whereas T 3 treatment increased the expression level of these genes.

show abstract

Section: Introductionmentioning

confidence: 99%

Triiodothyronine induces lipid oxidation and mitochondrial biogenesis in rat Harderian gland

Santillo

Burrone

Falvo

et al. 2013

Journal of Endocrinology

View full text Add to dashboard Cite

show abstract

“…In the green frog, Rana esculenta , a seasonally breeding species, HG is a seromucoid acinar gland that is sexually monomorphic and displays seasonal changes in secretory activity: the activity reaches a maximum during the hottest months and is at medium‐low levels in the remaining months (Di Matteo et al, 1989). Indeed, temperature has been found to be the main exogenous factor regulating this seasonal secretory activity (Minucci et al, 1990). During this annual cycle, RNA synthesis in the glandular cells varies in line with gland activity (Chieffi Baccari et al, 1992a).…”

mentioning

confidence: 99%

D‐aspartate modulates transcriptional activity in Harderian gland of frog, Rana esculenta: Morphological and molecular evidence

Raucci¹,

Santillo²,

D’Aniello

et al. 2005

Journal Cellular Physiology

View full text Add to dashboard Cite

In the green frog, Rana esculenta, a substantial amount of D-aspartate (D-Asp) is found endogenously within the Harderian gland (HG) following its synthesis from L-aspartate (L-Asp) by an aspartate racemase. The frog HG is an orbital seromucoid gland that displays seasonal changes in secretory activity. Our in vivo experiments, consisting of i.p. injection of 2.0 mumol/g b.w. D-Asp in frogs collected during two periods of differing glandular activity (high or medium-low secretory activity), revealed that HG can to take up and accumulate D-Asp and that this amino acid may modulate the exocrine secretion through a kinase pathway. At a time when the gland shows relatively low secretory activity, i.p. administration of D-Asp rapidly induced activation of ERK1 and an increase in cells active in RNA synthesis. This increase in transcriptional activity was followed by a significant increase in mucous secretion. By contrast, administration of exogenous D-Asp when HG was showing high activity rapidly induced inhibition of both ERK1 and transcriptional activity. Since D-Asp is known to be recognized by receptors for N-methyl-D-aspartic acid (NMDA), it is possible that in the HG, D-Asp mediated NMDA activation may enhance the kinase pathway. The above activation of opposing stimulatory and inhibitory processes could reflect different levels of NMDA-receptor activity, which could vary as a function of the level of gland activity. This study provides the first evidence of a role for this excitatory amino acid in exocrine secretion. The effects of D-Asp in HG appear to be specific since they were not seen in frogs treated with other D- or L-amino acids with known excitatory effects on neurosecretion.

show abstract

“…1996). In some anurans the Harderian gland shows seasonal changes (Minucci et al. 1990; Chieffi Baccari et al.…”

Section: Introductionmentioning

confidence: 99%

The nasolacrimal duct of anuran amphibians: suggestions on its functional role in vomeronasal perception

Nowack

Wöhrmann-Repenning

2010

Journal of Anatomy

View full text Add to dashboard Cite

Tear secretions discharged by the Harderian gland are suggested to function as a solvent for molecules sensed by the vomeronasal organ (VNO) in anurans. It has been assumed that chemical stimuli are absorbed at the surface of the eye to be carried -together with the lacrimal fluid -into the nasal cavity via the nasolacrimal duct. In the study presented herein, we examined the intranasal anatomy of 10 different anuran species to analyse the opening region of the nasolacrimal duct and its functional relationship with the VNO and the external naris. In addition, vital staining of the nasal cavities was conducted. Our results indicate that stimuli reaching the VNO are more likely to be ingested through the nostril than via the eye. In many cases the intranasal orifice of the nasolacrimal duct shows a close proximity to the external naris and simultaneously we observed a noticeable distance to the VNO. We suggest that the secretions of the Harderian gland are carried to the external naris by the nasolacrimal duct, where they bind chemical stimuli that are subsequently actively transported into the VNO. In some of the investigated species the opening region of the tear duct was situated in a more caudal part of the nasal cavity and closer to the VNO. In these cases a conspicuous system of channels can be found, which is suspected to carry the intruding medium of smell from the nostril to the nasolacrimal aperture.

show abstract

Influence of light and temperature on the secretory activity of the harderian gland of the green frog, Rana esculenta

Cited by 18 publications

References 7 publications

Triiodothyronine induces lipid oxidation and mitochondrial biogenesis in rat Harderian gland

Triiodothyronine induces lipid oxidation and mitochondrial biogenesis in rat Harderian gland

D‐aspartate modulates transcriptional activity in Harderian gland of frog, Rana esculenta: Morphological and molecular evidence

The nasolacrimal duct of anuran amphibians: suggestions on its functional role in vomeronasal perception

Contact Info

Product

Resources

About