In adult frogs we make serial ultrathin sections from close appositions between terminals of propriospianal actions and dendrites of spinal motoneurons and identifz the real sznaptic contacts

In adult frogs we make serial ultrathin sections from close appositions between terminals of propriospianal actions and dendrites of spinal motoneurons and identifz the real sznaptic contacts Morphological, physiological investigations and computer simulation of spinal neuronal network involved in locomotion

1. Premotor interneuron - motoneuron connections in the spinal cord of the frog

We have detected close appositions between the terminals of propriospinal axons and dendrites of spinal motoneurons in our earlier studies. In this project we make serial ultrathin sections from these areas in order to recognize the real synaptic contacts. We shall estimate the functional significance of the identified synaptic contacts located on different parts of the dendritic trees of spinal motoneurons by using computer simulation of the dendritic impulse propagation.

2. Investigations of spinal network producing swimming in Xenopus embryo

We will use a large scale population model of central pattern generator located in the spinal cord of the Xenopus embryo to study

the spinal interneurons responsible for the initiation and maintance of longitudinal and bilateral coordination of the body during swimming,

the changes in number and distribution of active spinal interneurons along the spinal cord during swimming,

the significance of gap juctions between the motoneurons in the maintance of stability during swimming.

3. The role of zinc in rhythmic motor pattern in the mammalian spinal cord

We will investigate possible colocalization of zinc with inhibitory neurotransmitters in the mammalian spinal cord. The zinc will be revealed by using modified Timm`s method and inhibitory amino acids will be detected with anti-GABA and anti-glycin antibodies by postembedding immunocytochemical methods. We will investigate the role of the zinc in spinal synapses with patch clamp methods. We will apply different concentrations of zinc in the chamber and monitor how the zinc modifies the synaptic currents evoked by GABA and glycin.