* Genetic absence of the vesicular inhibitory amino acid transporter differentially regulates respiratory and locomotor motor neuron development.
- During mid to late embryonic development (E13 to birth in mice), the neuromotor system is refined by reducing motor neuron (MN) numbers and establishing nascent synaptic connections onto and by MNs. Concurrently, the response to GABAergic and glycinergic synaptic activity switches from postsynaptic excitation to inhibition. Our previous studies on mutant mice lacking glycinergic transmission or deficient in GABA suggests that altered MN activity levels during this developmental period differentially regulates MN survival and muscle innervation for respiratory and non-respiratory motor pools. To determine if combined loss of GABAergic and glycinergic transmission plays a similar or exaggerated role, we quantified MN number and muscle innervation in two respiratory (hypoglossal and phrenic) and two locomotor (brachial and lumbar) motor pools, in mice lacking vesicular inhibitory amino acid transporter, which display absent or severely impaired GABAergic and glycinergic neurotransmission. For respiratory MNs, we observed significant decreases in MN number (-20 % hypoglossal and -36 % phrenic) and diaphragm axonal branching (-60 %). By contrast, for non-respiratory brachial and lumbar MNs, we observed increases in MN number (+62 % brachial and +84 % lumbar) and axonal branching for innervated muscles (+123 % latissimus dorsi for brachial and +61 % gluteal for lumbar). These results show that combined absence of GABAergic and glycinergic neurotransmission causes distinct regional changes in MN number and muscle innervation, which are dependent upon the motor function of the specific motor pool.
Overview of verb observe
The verb observe has 9 senses (first 8 from tagged texts)
1. (39) detect, observe, find, discover, notice -- (discover or determine the existence, presence,
or fact of; "She detected high levels of lead in her drinking water"; "We found traces of lead in
the paint")
2. (17) note, observe, mention, remark -- (make mention of; "She observed that his presentation took
up too much time"; "They noted that it was a fine day to go sailing")
3. (12) note, take note, observe -- (observe with care or pay close attention to; "Take note of this
chemical reaction")
4. (10) observe -- (watch attentively; "Please observe the reaction of these two chemicals")
5. (4) respect, honor, honour, abide by, observe -- (show respect towards; "honor your parents!")
6. (3) observe, celebrate, keep -- (behave as expected during of holidays or rites; "Keep the
commandments"; "celebrate Christmas"; "Observe Yom Kippur")
7. (2) watch, observe, follow, watch over, keep an eye on -- (follow with the eyes or the mind;
"Keep an eye on the baby, please!"; "The world is watching Sarajevo"; "She followed the men with the
binoculars")
8. (1) observe, keep, maintain -- (stick to correctly or closely; "The pianist kept time with the
metronome"; "keep count"; "I cannot keep track of all my employees")
9. observe, keep -- (conform one's action or practice to; "keep appointments"; "she never keeps her
promises"; "We kept to the original conditions of the contract")
Overview of adj observed
The adj observed has 1 sense (first 1 from tagged texts)
1. (7) ascertained, discovered, observed -- (discovered or determined by scientific observation;
"variation in the ascertained flux depends on a number of factors"; "the discovered behavior norms";
"discovered differences in achievement"; "no explanation for the observed phenomena")
--- WordNet end ---