Rogelio O Arellano

Learn More
In mouse luteinized-granulosa cells (MGLC), ATP induces an increase in intracellular Ca2+ concentration by stimulating phospholipase C (PLC) associated with purinergic receptors, leading to production of inositol 1,4,5-trisphosphate (IP3) and subsequent release of Ca2+ from intracellular stores. In this study, we examined the cross-talk between the(More)
1. Native Xenopus oocytes were voltage clamped and exposed to Ringer solutions containing low concentrations of divalent cations. Oocytes, held at -60 mV, developed a reversible non-inactivating smooth inward current (Ic) associated with an increase in membrane conductance. 2. Ic was selectively carried by cations (Na+, K+), indicating that the current was(More)
Conus californicus belongs to a genus of marine gastropods with more than 700 extant species. C. californicus has been shown to be distantly related to all Conus species, but showing unusual biological features. We report a novel peptide isolated from C. californicus with a significant inhibitory action over neuronal voltage-gated calcium channels. The new(More)
BACKGROUND Granulosa cells play an important endocrine role in folliculogenesis. They mobilize Ca2+ from intracellular stores by a coordinated action between 1,4,5 inositol trisphosphate and ryanodine receptors (IP3R and RyR). The aim of this study was to explore the isoforms of IP3Rs expressed in mouse C57BL/6 NHsd granulosa cells, characterizing their(More)
1. Ionic current responses elicited by acetylcholine (ACh) in follicle-enclosed Xenopus oocytes (follicles) were studied using the two-electrode voltage-clamp technique. ACh generated a fast chloride current (Fin) and inhibited K+ currents gated by cAMP (IK,cAMP) following receptor activation by adenosine, follicle-stimulating hormone or noradrenaline.(More)
The effect of pH was tested on the junction between crayfish lateral axons. By means of a glass capillary inserted into one of the axons, one side of the nunction was perfused with solutions of known pH while the junctional resistance,R j, was monitored. Integrity of the gap junction was checked electron microscopically.R j remained unchanged when the pH of(More)
Folliculogenesis modulation via distinct neurotransmitters is a well-documented phenomenon. Intraovarian purinergic signaling mechanisms have been identified previously in different species. However, the molecular elements involved and the physiological role of this purinergic signaling remain to be elucidated. Here, studies using RT-PCR amplification,(More)
The mechanism of apoptosis has been recognized as an important event in processes such as cellular development and homeostasis, as well as degenerative conditions like cancer. Prostate cancer during its advanced stages develops androgen independent cells that ultimately overgrow and promote metastatic events. Our group employing androgen independent LNCaP(More)
In this study, we determined hemolysis activity in human and sheep erythrocytes, and characterized the electrical responses in Xenopus oocyte membrane elicited by the venom of the jellyfish Cassiopea xamachana (Cx). The Cx venom produced hemolysis in both species, being more potent on human red cells. The electrophysiological study showed that the Cx venom(More)