The primary reproductive behavior of female quadrupeds is known as lordosis which is the bending of vertebral column during intercourse. This behavior depends on the actions of estrogens followed by progestin in cells within defined neuronal groups in the hypothalamus and midbrain. The main neural circuit for lordosis behavior is well established. Estrogen-dependent transcription in ventromedia...

MicroRNAs (miRNAs) are evolutionarily conserved, 18- to 25-nucleotide, non-protein coding transcripts that posttranscriptionally regulate gene expression during development. miRNAs also occur in postmitotic cells, such as neurons in the mammalian central nervous system, but their function is less well characterized. We investigated the role of miRNAs in mammalian midbrain dopaminergic neurons (...

The cat's pons was isolated by two brainstem transections, at the junction of medulla and pons and at the junction of pons and midbrain. In the deafferented pons the EEG activity was virtually absent, whereas the spatial density of active units and the rate of their spontaneous spike activity were at a high level. In the pons of control preparations with brainstem transected only at the ponto-m...

After neonatal damage to the midbrain tectum, hamsters exhibit as adults substantially reorganized retinal projections to the thalamus and midbrain. These experiments investigated the pattern of acquisition of a range of visuomotor capacities in hamsters with neonatal tectal damage, and the role of visual experience in this acquisition, by examining the time course of visuomotor development and...

Data from studies with humans have suggested that abnormalities of midbrain structures, including the periaqueductal gray matter (PAG), could be involved in the neurobiology of panic disorder (PD). The electrical stimulation of the PAG in neurosurgical patients induces panic-like symptoms and the effect of drugs that are effective in the treatment of PD in the simulation of public speaking mode...

The isthmic organizer, which is located at the midbrain-hindbrain boundary, plays an essential role in development of the midbrain and anterior hindbrain. It has been shown that homeobox genes regulate establishment of the isthmic organizer, but the mechanism by which the organizer is maintained is not well understood. Here, we found that, in mice doubly mutant for the basic helix-loop-helix ge...

Isolated spontaneous midbrain hemorrhages are rare because they are usually secondary to hemorrhages from inferior structures such as the pons and cerebellum, or superior structures such as the thalamus and putamen. While the etiologies are largely unidentified, the most common ones are vascular malformations and bleeding diathesis with hypertension being relatively uncommon. We report midbrain...

Neural adaptation is central to sensation. Neurons in auditory midbrain, for example, rapidly adapt their firing rates to enhance coding precision of common sound intensities. However, it remains unknown whether this adaptation is fixed, or dynamic and dependent on experience. Here, using guinea pigs as animal models, we report that adaptation accelerates when an environment is re-encountered-i...

and ectopic expression, we demonstrated that Gata2 regulates GABAergic neuron development in the midbrain, but not in the rhombomere1. Without Gata2, all the precursors in the embryonic midbrain fail to activate GABAergic neuron-specific gene expression and switch to a glutamatergic phenotype instead. Surprisingly, this fate switch is also observed throughout the neonatal midbrain, except for t...

Ascending projections to the thalamus from a midbrain somatosensory area were investigated in a reptile, Caiman crocodilus. Connections were determined utilizing horseradish peroxidase (HRP) neurohistochemistry in which tetramethylbenzidine was the chromogen. Anterograde experiments, in which HRP injections were placed into the midbrain, revealed bilateral projections to the medialis complex of...