A functional study on L-type calcium channels in granulosa cells of small follicles in laying and forced molt hens.

To investigate Ca(2+) dynamics in earlier phases of follicular development we compared the resting [Ca(2+)](i) and tested the functional responses to agonist/antagonist of L-type voltage-operated calcium channels (VOCCs) in small follicles GCs from hens during oviposition (O-GCs) and forced molt (M-GCs), using the microspectrofluorimetric [Ca(2+)](i) imaging. O-GCs were obtained from prehierarchical follicles (F(6)-F(5)-F(4)<8mm). In basal and agonist/antagonist stimulated M-GCs we did not observe a change in the [Ca(2+)](i) under any of condition in all cells analyzed.

Reduction of the olfactory cognitive ability in horses during preslaughter: stress-related hormones evaluation.

As horses may perceive several odour signals of danger at slaughter, application of mentholated ointment to their nostrils may limit their perception of danger. To assess the effect of the application of a mentholated ointment to horse nostrils on the stress response during pre-slaughter handling, plasma levels were evaluated for cortisol, beta-endorphin, epinephrine and norepinephrine prior to and after stunning. Twenty draught-type horses were divided into control (n=10) and treated (n=10) groups and a mentholated ointment applied to the nostrils of the treated horses following blood sampling in lairage 45 min prior to slaughter.

Delta opioid receptor on equine sperm cells: subcellular localization and involvement in sperm motility analyzed by computer assisted sperm analyzer (CASA).

Background: Opioid receptors and endogenous opioid peptides act not only in the control of nociceptive pathways, indeed several reports demonstrate the effects of opiates on sperm cell motility and morphology suggesting the importance of these receptors in the modulation of reproduction in mammals. In this study we investigated the expression of delta opioid receptors on equine spermatozoa by western blot/indirect immunofluorescence and its relationship with sperm cell physiology.

Methods: We analyzed viability, motility, capacitation, acrosome reaction and mitochondrial activity in the presence of naltrindole and DPDPE by means of a computer assisted sperm analyzer and a fluorescent confocal microscope.

Stress-related hormones in horses before and after stunning by captive bolt gun.

In this work the slaughter-linked plasma modifications of some stress-related hormones in horses subject to standardized butchering procedures were investigated in order to highlight the compromised animal welfare during pre-slaughter handling. During pre-slaughter, animals show strong hardship behavioural patterns, probably due to being under life-threatening conditions. Blood samples from 12 male horses, ageing from 3 to 5 years, were collected before slaughtering in lairage, and during exsanguination after stunning.

A semi-immobilizing system associated with microspectrofluorimetric and videoimaging analysis for intracytoplasmic calcium measurement in individual viable spermatozoa.

We describe a fast and simple method to monitor variations of intracytoplasmic calcium concentrations in very small and motile cells such as mammalian spermatozoa during measurement time. The method combines a procedure of sperm cells semi-immobilization with microspectrofluorimetric measurement of intracytoplasmic calcium concentrations supported by videoimaging that allows also a constant monitoring of viability during the time of calcium recording. In this paper we show that a semi-immobilization of individual viable spermatozoa can be obtained preparing the agar matrix in a two step procedure.

Disuse of rat muscle in vivo reduces protein kinase C activity controlling the sarcolemma chloride conductance.

Muscle disuse produced by hindlimb unloading (HU) induces severe atrophy and slow-to-fast fibre type transition of the slow-twitch soleus muscle (Sol). After 2 weeks HU, the resting ClC-1 chloride conductance (g(Cl)) of sarcolemma, which controls muscle excitability, increases in Sol toward a value typical of the fast-twitch EDL muscle. After 3 days of HU, the g(Cl) increases as well before initiation of fibre type transition.

Expression and immunolocalization of the mu-opioid receptor in human sperm cells.

The expression of the mu-opioid receptor in human sperm cells was investigated by immunocytochemistry and immunoblot analyses. Results demonstrated that the receptor is localized on the acrosomal region and the neck portion of the sperm head. These results suggest a possible role for the mu-opioid receptor in mediating the action of endogenous opioid peptides on sperm cells during the complex and poorly characterized cellular events that enable spermatozoa to fertilize oocytes.