targeted-toxins

Lehmann O, Bertrand F, Jeltsch H, Morer M, Lazarus C, Will B, Cassel JC (2002) 5,7-DHT-induced hippocampal 5-HT depletion attenuates behavioural deficits produced by 192 IgG-saporin lesions of septal cholinergic neurons in the rat. Eur J Neurosci 15(12):1991-2006. doi: 10.1046/j.1460-9568.2002.02037.x

Summary: Although past data has shown that the cholinergic system of the basal forebrain is intrinsic to learning and memory, more recent data suggests that other neurotransmitter systems are also involved, perhaps serving modulatory functions. The authors used 5,7-DHT injections alone or with intraseptal 192-Saporin (Cat #IT-01, 0.4 µg/side) injections in rats. The results demonstrate that serotonergic denervation of the hippocampus attenuates deficits produced by a cholinergic denervation of the septal region of the basal forebrain.

Usage: The authors used 192-Saporin, 0.4 µg/side intraseptal (Cat. #IT-01).

Related Products: 192-IgG-SAP (Cat. #IT-01)

Read the featured article in Targeting Trends.

Easton A, Ridley RM, Baker HF, Gaffan D (2002) Unilateral lesions of the cholinergic Basal forebrain and fornix in one hemisphere and inferior temporal cortex in the opposite hemisphere produce severe learning impairments in rhesus monkeys. Cereb Cortex 12(7):729-736. doi: 10.1093/cercor/12.7.729

Summary: The authors used a combination of basal forebrain lesioning using ME20.4-SAP (Cat. #IT-15) and surgery to isolate the inferior temporal cortex and medial temporal cortex from cholinergic afferents in rhesus monkeys. Testing of the treated animals demonstrated severe impairments in learning visual scenes and object-reward associations.

Related Products: ME20.4-SAP (Cat. #IT-15)

Porreca F, Ossipov MH, Gebhart GF (2002) Chronic pain and medullary descending facilitation. Trends Neurosci 25(6):319-325. doi: 10.1016/s0166-2236(02)02157-4

Objective: To examine the likelihood that sustained activation of descending modulatory pathways that facilitate pain transmission could underlie some states of chronic pain.

Summary: Rats treated with Dermorphin-SAP, either before or after spinal nerve ligation injury, did not display neuropathic pain behaviors, although normal nociceptive responses were intact.

Usage: Rostroventromedial medulla (RVM) injected with Dermorphin-SAP.

Related Products: Dermorphin-SAP / MOR-SAP (Cat. #IT-12)

See Also:

• Porreca F et al. Inhibition of neuropathic pain by selective ablation of brainstem medullary cells expressing the µ-opioid receptor. J Neurosci 21(14):5281-5288, 2001.

Risbrough V, Bontempi B, Menzaghi F (2002) Selective immunolesioning of the basal forebrain cholinergic neurons in rats: effect on attention using the 5-choice serial reaction time task. Psychopharmacology 164:71-81. doi: 10.1007/s00213-002-1170-7

Summary: The authors used 0.067 µg injections of 192-Saporin (Cat. #IT-01) into the nucleus basalis magnocellularis to investigate attentional performance in rats. The treated animals exhibited a very specific subset of attentional deficits, many centered around increased difficulty completing tasks in the presence of distractions.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Burgess SE, Gardell LR, Ossipov MH, Malan Jr TP, Vanderah TW, Lai J, Porreca F (2002) Time-dependent descending facilitation from the rostral ventromedial medulla maintains, but does not initiate, neuropathic pain. J Neurosci 22(12):5129-5136. doi: 10.1523/JNEUROSCI.22-12-05129.2002

Summary: Various indications, such as declining afferent discharge over time, suggest that the mechanisms involved in persistent neuropathic pain are different than those that initiate the pain. The authors have previously shown that cells expressing the mu-opioid receptor are involved in the descending pain pathway. In this work, the authors lesioned the rostral ventromedial medulla (RVM) in rats using 1.5 pmol in 0.5 µl of dermorphin-SAP (Cat. #IT-12) administered to each side of the RVM. Measurements of pain-related behavior show that mu-opioid receptor-expressing cells in the RVM are involved in the maintenance of heightened sensitivity to stimuli seen in neuropathic pain.

Related Products: Dermorphin-SAP / MOR-SAP (Cat. #IT-12)

Fraley GS, Dinh TT, Ritter S (2002) Immunotoxic catecholamine lesions attenuate 2DG-induced increase of AGRP mRNA. Peptides 23(6):1093-1099. doi: 10.1016/s0196-9781(02)00044-x

Summary: The authors investigated mRNA levels of both agouti gene-related protein (AGRP) and neuropeptide Y (NPY) in rats after lesioning the PVH with anti-DBH-SAP (42 ng in 200 nl, Cat. #IT-03). The results show that the increase in AGRP mRNA levels due to 2DG administration was completely blocked.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Galani R, Jeltsch H, Lehmann O, Bertrand F, Cassel JC (2002) Effects of 192 IgG-saporin on acetylcholinesterase histochemistry in male and female rats. Brain Res Bull 58(2):179-186. doi: 10.1016/s0361-9230(02)00775-x

Summary: Male rats were treated with estradiol, and 2-µg i.c.v. injections of 192-Saporin (Cat #IT-01).

Related Products: 192-IgG-SAP (Cat. #IT-01)

Bitner RS, Nikkel AL (2002) Alpha-7 nicotinic receptor expression by two distinct cell types in the dorsal raphe nucleus and locus coeruleus of rat. Brain Res 938:45-54. doi: 10.1016/s0006-8993(02)02485-x

Summary: Neuronal nicotinic acetylcholine receptors (nAChRs) are suspected to play a role in neurophysiological disorders such as schizophrenia, Alzheimer’s disease, and epilepsy. Whereas the molecular and cellular properties of these receptors have been well characterized, the role of nAChRs in the nervous system is as yet unclear. The authors injected rats intracerebroventricularly with 5 µg/5 µl of anti-DBH-SAP (Cat. #IT-03) to eliminate the noradrenergic nuclei. Using these data along with data acquired by elimination of serotonergic nuclei with 5,7-DHT, the authors showed that both noradrenergic nuclei in the locus coeruleus and serotonergic nuclei in the dorsal raphe nucleus express the alpha-7 nAChR subunit.

Related Products: Anti-DBH-SAP (Cat. #IT-03)

Zhu XO, de Permentier PJ, Waite PM (2002) Cholinergic depletion by IgG 192-saporin retards development of rat barrel cortex. Brain Res Dev Brain Res 136:1-16. doi: 10.1016/s0165-3806(02)00301-2

Summary: It has been shown that cholinergic afferents from the basal forebrain are necessary for normal cortical morphogenesis. However, the role of these projections in the development of the thalamocortical topographical map has not been investigated. Using the facial whisker barrel field in the rat somatosensory cortex as a development model, the authors administered 192-Saporin to newborn pups (0.1 µg, Cat. #IT-01). The data show a transient delay in the development of the barrel pattern over the first postnatal week.

Related Products: 192-IgG-SAP (Cat. #IT-01)

Birthelmer A, Dommes E, Jeltsch H, Cassel JC, Jackisch R (2002) Septal grafts and evoked acetylcholine release in the rat hippocampus after 192 IgG-saporin lesions. Neuroreport 13(7):973-976. doi: 10.1097/00001756-200205240-00015

Summary: The authors investigate the structural and behavioral effects of intrahippocampal grafts containing cholinergic neurons into a lesioned region of the brain. Previous studies in rats were complicated by the lack of a specific cholinergic lesioning agent. 0.4 µg 192-Saporin (Cat. #IT-01) in 0.4 µl was injected into the vertical limb of the diagonal band of Broca in rats, then 6 to 10 months later the animals received intrahippocampal grafts of septal cells containing cholinergic neurons. Measurement of noradrenaline and serotonin uptake indicate that the grafts were able to produce only modest cholinergic effects. The authors conclude that this may be a result of performing the graft too soon following administration of the immunotoxin.

Related Products: 192-IgG-SAP (Cat. #IT-01)