Related Experiment Video
Updated: Feb 7, 2026
Paradigms for Pharmacological Characterization of C. elegans Synaptic Transmission Mutants
Published on: August 18, 2008
Postnatal development of inhibitory synaptic transmission in the anterior piriform cortex
Grace Violeta Espinoza Pardo1, Aldo Bolten Lucion2, Maria Elisa Calcagnotto3
1Department of Physiology, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil; Neurophysiology and Neurochemistry of Neuronal Excitability and Synaptic Plasticity Laboratory, Department of Biochemistry, Institute of Basic Health Sciences, Universidade Federal do Rio Grande do Sul, Porto Alegre, RS, Brazil.
Insights
The development of inhibitory circuits in the anterior piriform cortex (aPC) matures with increased GABAergic transmission. Early olfactory deprivation had minimal impact on this maturation process in rat pups.
Area of Science:
- Neuroscience
- Developmental Biology
- Sensory Processing
Background:
- Inhibitory circuits in the anterior piriform cortex (aPC) are crucial for olfactory learning.
- Understanding the developmental trajectory of GABAergic transmission in the aPC is essential.
- Sensory experience can influence neocortical inhibitory circuit development.
Purpose of the Study:
- To investigate the normal development of GABAergic synaptic transmission in the rat aPC during early postnatal life.
- To examine the effects of early partial olfactory deprivation on this developmental process.
Main Methods:
- Whole-cell patch-clamp recordings were performed on layer 2/3 (L2/3) aPC pyramidal cells in rat pups.
- Recordings were conducted at two developmental stages: postnatal days (P) 5-8 and P14-17.
- Experiments included sham-operated and unilaterally naris-occluded animals to assess olfactory deprivation effects.
Main Results:
- Significant increases in spontaneous (sIPSC) and miniature (mIPSC) inhibitory postsynaptic current frequencies were observed from P5-8 to P14-17.
- mIPSC rise and decay times decreased with age, indicating faster inhibitory transmission.
- Olfactory deprivation showed complex effects: age-dependent increases in IPSC frequency were blunted ipsilaterally but enhanced contralaterally, while sIPSC kinetics were altered at P5-8.
Conclusions:
- GABAergic synaptic transmission in the aPC matures significantly during the first three postnatal weeks, characterized by increased inhibitory input frequency and faster kinetics.
- Early partial olfactory deprivation appears to have a limited impact on the overall maturation of GABAergic synaptic transmission in the aPC.
- These findings provide insights into the neural mechanisms underlying olfactory processing and odor preference learning development.
Abstract:
The morphological and functional development of inhibitory circuit in the anterior piriform cortex (aPC) during the first three postnatal weeks may be crucial for the development of odor preference learning in infant rodents. As first step toward testing this hypothesis, we examined the normal development of GABAergic synaptic transmission in the aPC of rat pups during the postnatal days (P) 5-8 and 14-17. Whole cell patch-clamp recordings of layer 2/3 (L2/3) aPC pyramidal cells revealed a significant increase in spontaneous (sIPSC) and miniature (mIPSC) inhibitory postsynaptic current frequencies and a decrease in mIPSC rise and decay-time constant at P14-P17. Moreover, as the development of neocortical inhibitory circuit can be driven by sensory experience, we recorded sIPSC and mIPSC onto L2/3 aPC pyramidal cells from unilateral naris-occluded animals. Early partial olfactory deprivation caused by naris occlusion do not affected the course of age-dependent increase IPSC frequency onto L2/3 aPC pyramidal cell. However, this age-dependent increase of sIPSC and mIPSC frequencies were lower on aPC pyramidal cells ipsilateral to the occlusion side. In addition, the age-dependent increase in sIPSC frequency and amplitude were more pronounced on aPC pyramidal cells contralateral to the occlusion. While mIPSC kinetics were not affected by age or olfactory deprivation, at P5-P8, the sIPSC decay-time constant on aPC pyramidal cells of both hemispheres of naris-occluded animals were significantly higher when compared to sham. These results demonstrated that the GABAergic synaptic transmission on the aPC changed during postnatal development by increasing inhibitory inputs on L2/3 pyramidal cells, with increment in frequency of both sIPSC and mIPSC and faster kinetics of mIPSC. Our data suggested that the maturation of GABAergic synaptic transmission was little affected by early partial olfactory deprivation. These results could contribute to unravel the mechanisms underlying the development of odor processing and olfactory preference learning.
More Related Videos
12:06Transmission Electron Microscopy as the Visualization Technique for Analysis of Circadian Synaptic Plasticity in the Mouse Barrel Cortex
Published on: August 19, 2025
11:31Ex Vivo Optogenetic Interrogation of Long-Range Synaptic Transmission and Plasticity from Medial Prefrontal Cortex to Lateral Entorhinal Cortex
Published on: February 25, 2022
Related Concept Videos
01:12Synaptic Signaling
01:09Synaptic Signaling
Most synapses are chemical, meaning an electrical impulse or action potential spurs the release of chemical messengers called neurotransmitters. The neuron sending the signal is called the presynaptic neuron, and the neuron receiving the signal is the postsynaptic neuron.
The presynaptic neuron fires an action potential that...
01:29Excitatory and Inhibitory Effects of Neurotransmitters
01:26Muscles of the Anterior Neck
01:21Association Areas of the Cortex
Prefrontal Association Area: This area is located in the frontal lobe and is involved in planning, decision-making, and moderating social behavior. It connects with primary motor areas,...
01:28Integration of Synaptic Events