The influence of steam pelleting and grinding on the nutritive value of Canola rapeseed for poultry

In an attempt to explain the poorer performance and lower fat digestibility often encountered with Canola seed diets, maize and soya bean diets containing 20% Canola seed or an equivalent amount of added fat (8%) from maize oil, Canola oil, tallow or an animal—vegetable blend fat, were given to broiler chicks. Although significant differences in $\text{feed}\text{gain}$ ratios and fat digestibility were noticed, all diets promoted good growth, and dietary fat appeared to be well utilized.In a second experiment, to reinvestigate the effects of mash vs. pelleted diets, marked improvements were noted in performance, and especially in the digestibility of the fat from Canola seed diets, in response to steam pelleting. Examination of the mash diet revealed approximately 6% whole Canola seeds and other seeds at various degrees of pulverization.A third experiment compared Canola seed passed once or twice through a hammer mill, either by itself or mixed 50:50 (w/w) with maize, before being mixed with other dietary ingredients. Again, whole seeds were noted in the ground material. The Canola seed mixed with maize and ground once had 26% whole seeds, while the seed ground twice by itself had no whole seeds but many that were little better than cracked. All diets were given as mash or as steam crumbles. Marked improvements in weight gain and $\text{feed}\text{gain}$ ratios and fat digestibility were noted for the crumbled vs. the mash diets. It is obvious that some of the variable results reported for Canola seed can be related to fineness of grind of the material. The steam pelleting process results in sufficient pulverization, or breaking up of the seed, to allow for optimum performance with diets containing up to 20% Canola seed. Heating per se might also be an important consideration in steam pelleting. One can conclude that up to 20% Canola seed can be used in steam-pelleted diets based on maize and soya bean meal without altering broiler performance.     

Receptor-like stereospecific binding of a pyrethroid insecticide to mouse brain membranes

A heterogeneous particulate fraction of mouse brain homogenates binds NRDC 157 (3-phenoxybenzyl [1$\text{R}$,$\text{cis}$]-3-(2,2-dibromovinyl)-2,2- dimethylcyclopropanecarboxylate), a potent pyrethroid insecticide, stereospecifically and with high affinity. Stereospecific binding is a minor component of total binding (2.8%); the remainder of observed binding is predominantly nonspecific and unsaturable. Stereospecific binding is half-saturated at 4×10^?8$\text{M}$ and fully saturated at concentrations in excess of 1×10^?7$\text{M}$. The stereospecific binding capacity of this preparation was 200–250 pmoles of NRDC 157 per gram equivalent of brain tissue (2.3–2.8 pmol/mg protein). This binding site may represent the neural receptor involved in the stereospecific toxic action of pyrethroids.     

Structure and action of heteronemertine polypeptide toxins Binding of cerebratulus lacteus toxin B-IV to axon membrane vesicles

The binding of the crustacean selective protein neurotoxin, toxin B-IV, from the nemertine Cerebratulus lacteus to lobster axonal vesicles has been studied. A highly radioactive, pharmacologically active derivative of toxin B-IV has been prepared by reaction with Bolton-Hunter reagent. Saturation binding and competition of ¹²⁵I-labeled toxin B-IV by native toxin B-IV have shown specific binding of ¹²⁵I-labeled toxin B-IV to a single class of binding sites with a dissociation constant of 5–20 nM and a binding site capacity, corrected for vesicle sidedness, of 6–9 pmol per mg membrane protein. This compares to a value of 3.8 pmol [³H]saxitoxin bound per mg in the same tissue. Analysis of the kinetics of toxin B-IV association ($\text{k}{}_{\mathrm{+1}}\text{=7.3·10}{}^5\text{M}{}^{\mathrm{?1}}\text{·s}{}^{\mathrm{?1}}$) and dissociation ($\text{k}{}_{\mathrm{?\; 1}}\text{=2·10}{}^{\mathrm{?3}}\text{s}{}^{\mathrm{?1}}$) shows a nearly identical $\text{K}{}_{\mathrm{<mtext>d</mtext>}}$ of about 3 nM. There is no competition of toxin B-IV binding by purified toxin from Leiurus quinquestriatus venom while Centruroides sculpturatus Ewing toxin I appears to cause a small enhancement of toxin B-IV binding.     

Determination of the kinetic constants of fructose transport and phosphorylation in the perfused rat liver

The kinetics of fructose uptake was determined in perfused rat liver during steady-state fructose elimination. On the basis of the corresponding values of fructose concentration in the affluent and in the effluent medium, and the fructose and ATP concentration in biopsies, the kinetics of membrane transport and intracellular phosphorylation in the intact organ was calculated according to a model system. Carrier-mediated fructose transport has a high $\text{K}{}_{\mathrm{<mtext>m</mtext>}}$ (67 mM) and $\text{V}$ (30 μmoles · min^?1 ·g^?1). The calculated kinetic constants of the intracellular phosphorylation were compared with values obtained with an acid-treated rat liver high speed supernatant (values given in parentheses). $\text{K}{}_{\mathrm{<mtext>m</mtext>}}$ with fructose 1.0 mM (0.7 mM), $\text{K}{}_{\mathrm{<mtext>m</mtext>}}$ with ATP 0.54 mM (0.37 mM), $\text{V}$ 10.3 μmoles · min^?1 · g^?1 (10.1 μmoles · min^?1 · g^?1, calculated on the basis of the highest measured rate of fructose uptake correcting the ATP concentration to saturating values). The kinetics of fructose uptake reveals that at Physiological fructose concentrations the membrane transport limits the rate of fructose uptake, thus protecting the liver from severe depletion of adenine nucleotides.     

Stereospecific 3H-nicotine binding to intact and solubilized rat brain membranes and evidence for its noncholinergic nature

³H-nicotine binding was performed on intact and solubilized rat brain membranes as well as membranes from the electric organ of the $\text{Torpedo}$ fish. The K_d for binding to intact and solubilized rat brain membranes was 5.6 × 10^?9 M and 1.1 × 10^?8M respectively, and the binding capacity 2.0 × 10^?14 and 3.0 × 10^?13 moles /mg protein respectively. The K_d for Torpedo membranes was 3.1 × 10^?7M and the binding capacity 6.8 × 10^?13 moles/mg protein. The binding was stereospecific with the affinity of the (?)-nicotine being about 8 times greater than the (+)-nicotine with all three preparations. The relative affinity for the nicotine binding site of nicotinic cholinergic drugs was considerably less in rat brain than in $\text{Torpedo}$ membranes, where the sites are mainly cholinergic. A comparison was made of the ability of a variety of cholinergic drugs and nicotine derivatives to compete with ³H-nicotine binding and their relative pharmacologic potency to produce or inhibit a characteristic prostration syndrome caused by (?)-nicotine administered intraventricularly to rats. From such studies it was concluded that nicotine, in part, may be interacting at noncholinergic sites in rat brain.     

The aging leydig cell: VII. Cytoplasmic estradiol receptors

Plasma estradiol and cytosolic estradiol receptor levels of testes were determined in a group of young (2–3 months) and old (24 months) Sprague-Dawley rats. Estradiol binding sites for the young rats averaged 5.6 ± 0.3 fmol/mg protein ($\text{x}\text{±}\text{SE, n}\text{=12}$), which was comparable to that of the old rats, 5.7 ± 0.3 fmol/mg protein (n=12). Using Scatchard analyses, the association constants at equilibrium of estradiol receptor binding of the old and young rats were the same, 6.1 × 10¹⁰M^?1. Plasma estradiol levels were also similar in both groups-19.6 ± 2.8 pg/ ml (n=14) for the young and 19.2 ± 2.6 pg/ml (n=10) for the old rats. Our results suggest that impaired testosterone biosynthesis in old rats was not due to elevated plasma estradiol levels or to differences in testicular estradiol receptor content.     

Rapid kinetic studies of calmodulin interactions with calcium and troponin I as monitored by anthroylcholine fluorescence

Anthroylcholine was utilized as an extrinsic fluorescent probe in rapid kinetic studies of calcium dissociation from calmodulin (k_off = 10 S^?1) and the calmodulin-troponin I complex (k_off = 6 S^?1). At concentrations lower than 70 μM, the mechanism of dye binding agreed with the simple kinetic scheme in which the dye binds exclusively to the respective calcium complexes of calmodulin and calmodulin-troponin I. The sensitivity of anthroylcholine also made possible the estimation of values for the association (1.0 ± 0.8) × 10⁸$\text{M}{}^{\mathrm{?1}}$ S^?1) and dissociation rate constants (2 ± 170 S^?1) for troponin I binding to the calcium₄-calmodulin complex.     

Identification of ortho-octopamine and meta-octopamine in mammalian adrenal and salivary gland.

$\text{Ortho}$- and $\text{meta}$- octopamine have been identified in beef and rat adrenal gland and in rat salivary gland by means of gas chromatography-mass spectrometry. The tritrifluoroacetyl derivatives of $\text{ortho}$-, $\text{meta}$- and $\text{para}$- octopamine were resolved by gas chromatography and shown to produce two characteristic ions at $\text{m/e}$ 315 and $\text{m/e}$ 328. The di-O-trimethylsilyl-N-trifluoroacetyl derivatives of these three isomers were also resolved by gas chromatography and shown to produce a characteristic ion at $\text{m/e}$ 267. Biological samples were homogenized in formic acid:acetone, subjected to ion-exchange chromatography and then derivatized. When the derivatized biological extracts were examined for each characteristic ion, peaks were observed at the exact retention times of the standards. The three isomers are present in adrenal gland in concentrations of ～1 μg g^?1 and in rat salivary gland in concentrations of ～0.1 μg g^?1. This evidence confirms a previous report of the presence of $\text{m}$-octopamine in rat salivary gland measured by a radiochemical enzyme assay and is the first report of the presence of $\text{o}$-octopamine in biological tissue.     

Binding of opiates and endogenous opioid peptides to neuroleptic receptor sites in the corpus striatum.

Some opiates with morphinan- and benzomorphan-structures possess affinities for neuroleptic receptors as revealed by their abilities to compete with ³H-spiroperidol for common binding sites in rat striatum $\text{in vitro}$ (IC₅₀ in the range between 10^?6 and 10^?5M). The binding of these opiates to neuroleptic receptors appears to be of pharmacological significance, since $\text{in vivo}$ studies in mice revealed a small but significant displacement of spiroperidol by high doses of the opiate antagonist levallorphan from specific binding sites in the striatum. In addition, there exists some correlation between the ability of opiates to bind to neuroleptic receptor sites $\text{in vitro}$ and their potency to evoke “bizarre behavior” in rats $\text{in vivo}$. In contrast, a wide variety of other opiates having morphine-, morphinone- or oripavine-structure showed no affinity for neuroleptic binding sites $\text{in vitro}$ (IC₅₀ greater than 10^?4 M). Of the opioid peptides (methionine-enkephalin, leucine-enkephalin and β-endorphin) none has an affinity for neuroleptic binding sites. A variety of other peptides were also investigated but did not interfere with spiroperidol binding. Only ACTH showed a moderate affinity for neuroleptic binding sites.     

Ontogeny of the mammalian insulin receptor: Studies of human and rat fetal liver plasma membranes

Insulin binding to human fetal plasma liver membranes was studied in preparations segregated into three pools according to length of gestation: 15–18 weeks (Pool A), 19–25 weeks (Pool B), and 26–31 weeks (Pool C). Receptor numbers, calculated by extrapolation of Scatchard plots to the X axis, increased from 25 × 10¹⁰ sites per 100 μg protein in the youngest group (Pool A) to 46 × 10¹⁰ sites per 100 μg protein in Pool B. No further increase in receptor number was seen in Pool C. The affinity constant for insulin at tracer concentrations, $\text{K}{}_{\mathrm{<mtext>e</mtext>}}$ (“empty site”), was 1.53 × 10⁸M^?1 in Pool A and was only slightly higher than $\text{K}{}_{\mathrm{<mtext>f</mtext>}}$ (“filled site”). $\text{K}{}_{\mathrm{<mtext>e</mtext>}}$ was higher in Pool B, 1.75 × 10⁸M^?1, and in Pool C reached a value of 5.63 × 10⁸M^?1. In Pool C $\text{K}{}_{\mathrm{<mtext>f</mtext>}}$ was 2.3 × 10⁸M^?1. Insulin binding of liver plasma membranes from rat fetuses aged 14, 16, 18, and 21 (term) days and adults was also studied. Maximum binding capacity tended to increase with gestational age and was 130 × 10¹⁰ sites per 100 μg protein at term, which was in excess of that found in adult rats (89–90 × 10¹⁰). In addition, $\text{K}{}_{\mathrm{<mtext>e</mtext>}}$ increased from 0.75 × 10⁸M^?1 at 14 days to 3.02 × 10⁸M^?1 at term, a value higher than that found in pregnant and nonpregnant adults. Dissociation of insulin in the presence of high concentrations of insulin was significantly enhanced in tissues from 18-day and term fetuses and adults, but not in membranes from fetal rats aged 14 and 16 days. These data appear to indicate that site-site interactions are not present in early fetal existence. These changes in insulin binding with increased length of gestation are not ascribable to changes in relative proportions of hematopoietic and parenchymal tissue. Human fetal plasma liver membranes demonstrated elevated insulin binding with increased gestational age, but comparison of fetal and adult liver could not be done. However, newborn human infants have been shown to have a higher capacity for binding insulin to circulating monocytes than adults. Also, human fetuses apparently lack the capability to diminish monocyte receptors in the presence of hyperinsulinemia. These experiments show that an increase in insulin receptor binding capacity and affinity also occurs in the liver of the rat fetus at term as compared to the adult rat. The reasons and mechanisms underlying enhanced capacity for insulin binding by fetal and newborn members of human and rodent species are not known.     

Binding of [3H]methyltrienolone to androgen receptor in rat liver

The synthetic androgen methyltrienolone is superior to testosterone and androstenedione for the measurement of androgen receptor in tissues where the native ligands are metabolized into inactive derivatives. [³H]Methyltrienolone binds with a high affinity to androgen receptor in cytosol prepared from male rat livers, as the Scatchard analysis revealed that the K_d value was 3.3 · 10^?8 M and the number of binding sites was 35.5 fmol/mg protein. Since methyltrienolone also binds glucocorticoid receptor which exists in rat liver, the apparent binding of androgen receptor is faulty when measured in the presence of glucocorticoid receptor. The binding of methyltrienolone to glucocorticoid receptor can be blocked by the presence of a 100-fold molar excess of unlabeled synthetic glucocorticoid, triamcinolone acetonide, without interfering in its binding to androgen receptor, because triamcinolone does not bind to androgen receptor. Triamcinolone-blocked cytosol exhibited that the K_d value was 2.5 · 10^?8 M and the number of binding sites was 26.3 fmol/mg protein, indicating a reduction to $\text{3}\text{4}$ of that in the untreated cytosol. The profile of glycerol gradient centrifiguration indicated that [³H]methyltriemolone-bound receptor migrated in the 8–9 S region in both untreated and triamcinolone-blocked cytosols, but the 8–9 S peak in triamcinolone-blocked cytosol was reduced to about $\text{3}\text{4}$ of that of untreated cytosol.     

A study of the relationships between carbon tetrachloride-induced lipid peroxidation and liver damage in rats pretreated with vitamin E

The relationships between the peroxidation of musomal lipids and the early liver damage have been investigated in rats pretreated with progressively higher doses of α-tocopherol (vit. E) and intoxicated with various amounts of carbon tetrachloride.Pretreatment of rats with vit. E at 25 $\text{mg}\text{100g}$ body wt. has minor effects on both the peroxidation of musomal lipids and the liver triglyceride accumulation in rats poisoned with CC1₄ at 250 $\text{μl}\text{100g}$ body wt. However, a decrease of the peroxidative reaction and of the liver steatosis occurs when the rats are pretreated with progressively higher doses of vit.E. A close correlation exists between the two phenomena, when the intoxication is accomplished with CC1₄ at 250 $\text{μ1}\text{100 g}$ body wt. Also, the musomal concentration of α-tocopherol is strictly correlated to both the decrease of musomal lipoperoxidation and the decrease of liver triglyceride accumulation. The CCl₄-induced impairment of musomal glucose-6-phosphatase and the incorporation of ¹⁴C from ¹⁴CC1₄ into liver musomal lipids are not affected by vit. E pretreatment.The extent of musomal lipoperoxidation is not correlated to the liver triglyceride accumulation when vit. E-pretreated rats are given CC1₄ at 25 or 2.5 $\text{μ1}\text{100 g}$ body wt. However, a correlation between lipoperoxidation and liver steatosis occurs when non-pretreated rats are challenged with the three different doses of the halogenated hydrocarbon.     

Dopamine-stimulated cyclic AMP and binding of [3H]dopamine in acini from dog pancreas

Dispersed acini from dog pancreas were used to examine the ability of dopamine to increase cyclic AMP cellular content and the binding of [³H]dopamine. Cyclic AMP accumulation caused by dopamine was detected at 1·10^?8 M and was half-maximal at $\text{7.9±3.4·10}{}^{\mathrm{?7}}\text{M}$. The increase at 1·10^?5 M, (7.5-fold) was equal to the half-maximal increase caused by secretin at 1·10^?9 M. Haloperidol, a dopaminergic receptor antagonist inhibited cyclic AMP accumulation caused by dopamine. The IC₅₀ value for haloperidol, calculated from the inhibition of cyclic AMP increase caused by 1·10^?5 M dopamine was $\text{2.3±0.9·10}{}^{\mathrm{?6}}\text{M}$. Haloperidol did not alter basal or secretin-stimulated cyclic AMP content. [³H]Dopamine binding was studied on the same batch of cells as cyclic AMP accumulation. At 37°C, it was rapid, reversible, saturable and stereospecific. The $\text{K}{}_{\mathrm{<mtext>d</mtext>}}$ value for high affinity binding sites was $\text{0.43±0.1·10}{}^{\mathrm{?7}}\text{M}$ and $\text{4.7±1.6·10}{}^{\mathrm{?7}}\text{M}$ for low affinity binding sites. The concentration of drugs necessary to inhibit specific binding of dopamine by 50% was $\text{1.2±0.4·10}{}^{\mathrm{/t-7}}\text{M}$ noradrenaline, 2·10^/t-7 M epinine, $\text{4.1±1.8·10}{}^{\mathrm{/t-6}}\text{M}$ fluphenazine, $\text{8.0±1.6·10}{}^{\mathrm{/t-6}}\text{M}$ haloperidol, $\text{4.2±1.2·10}{}^{\mathrm{?6}}\text{M}$cis-flupenthixol, $\text{2.7±0.4·10}{}^{\mathrm{?5}}\text{M}$trans-flupenthixol, $\text{>1·10}{}^{\mathrm{?5}}\text{M}$ apomorphine, sulpiride, naloxone and isoproterenol.     

Structural properties of the membrane of intact human spermotozoa: A study with fluorescent probes

The properties of the membrane of intact, metabolically active, human persmatozoa have been studied by the use of 1-anilino-8-napthalene sulfonate (ANS). By fluorescence microscopy it was found that at neutral pH ANS is bound exclusively to the membrane of the entire sperm with some preferential binding to the midpiece, while at low pH some preferential binding to the aerosome was observed. By spectrofluorimetry, fluorescence was found to be enhanced 48-fold on binding of ANS to the spermatozoal membrane, with a 50-nm shift in the emission spectrum of the bound dye. $\text{2.47 ± 0.02}$ nmoles of ANS were bound per 10⁶ spermatozoa ($\text{K=2.3–10}{}^{\mathrm{?5}}\text{M}$). Scatchard plots indicate that all the binding sites on the spermatozoal membrane have similar binding characteristics with aZ value of 84.8. Energy transfer with an efficiency of 7% was found for recently ejaculated spermatozoa. The fluorescence of bound ANS depends on the pH of the medium and possibly on the metabolic state of the cell, since addition of succinate or fructose produces an enhancement of fluorescence, while addition of glucose results in a decrease of this parameter. These changes are inhibited by the presence of cyanide.     

Inhibition by zinc of the binding of C1 to antigen-antibody complexes

Zinc sulphate in the range of 10^?4 to 2×10^?5 M prevents the binding of $\text{C}\text{1}$ to antigen antibody complexes, and the initation of the cascade of events in the classical complement pathway leading to cell lysis. Other heavy metals, Co⁺⁺, Cd⁺⁺, Cu⁺⁺, or Mn⁺⁺ were without effect in this concentration range. Zinc was ineffective when added after $\text{C}\text{1}$ was bound and failed to displace $\text{C}\text{1}$ which was already bound to antigen antibody complexes. The ability of zinc to regulate the binding of the zymogen or activated form of $\text{C}\text{1}$ to antigen-antibody complexes represents a new method of controlling the initiation of the classical complement pathway.     

Stereospecific interaction of opiate narcotics in binding of 3H-dihydromorphine to membranes of rat brain

Membranes from homogenates of corpus striatum bound ³H-dihydromorphine in a saturable fashion with a Km value of 1 × 10^?9M. The binding of ³H-dihydromorphine to the membranes was reduced to about 10% by 10^?7M levorphanol but not by 10^?7M dextrorphan. The binding of ³H-dihydromorphine became less sensitive to 10^?7M levorphanol when the concentration of ³H-dihydromorphine was greater than 2 × 10^?9M. Other opiate narcotics, e.g. morphine and $\text{l}$-methadone, were as effective as levorphanol in competition for the binding ³H-dihydromorphine with ED₅₀ values of 2–4 × 10^?9M. $\text{d}$-Methadone and dextrorphan were about 1/50 and 1/2000 as effective as their respective levo-isomers. The opiate antagonist, naloxone, also competed effectively for the binding sites with an ED₅₀ value of 3.3 × 10^?9M. Substances like acetylcholine, choline, serotonin, norepinephrine and dopamine were ineffective. Only ionophores specific for divalent cations stimulated the binding of ³H-dihydromorphine suggesting that some endogenous divalent cations may be inhibitory to the binding of the opiate narcotic. The receptors of ³H-dihydromorphine probably exist in the membranes of nerve endings and have a density of 6 × 10¹² sites per g in corpus striatum. We conclude that the described technique can successfully detect the opiate narcotic receptors in the central nervous system without the usual method of displacement.     

Stimulation of caffeine metabolism in the rat by 3-methylcholanthrene

Groups of adult male rats treated with 3-methylcholanthrene, phenobarbital or vehicles alone, were administered caffeine either orally or intravenously. Serum caffeine concentrations were measured by radioimmunoassay. In vehicle and phenobarbital pretreated animals, caffeine elimination kinetics were non-linear. In control animals, the $\text{in}$$\text{vivo}$ apparent Km was 8 μg·ml^?1 (40 μM) and the apparent Vmax was 0.1 μg·ml^?1·min^?1 (0.5 μM·min^?1). Phenobarbital pretreatment did not change the apparent Km but slightly increased the apparent Vmax. 3-Methylcholanthrene pretreatment dramatically altered the elimination kinetics of caffeine, whether caffeine was given orally or intravenously. The elimination of caffeine from serum of 3-methylcholanthrene pretreated rats was first order with a $\text{t}\text{1}\text{2}$ of approximately 14 minutes.Our results are consistent with the proposed involvement of the cytochromes P-450 monooxygenase system in the elimination of caffeine. In addition, our results suggest that caffeine is a moderately poor substrate for the cytochromes P-450 present in control and phenobarbital-pretreated rats, but a particularly good substrate for the form(s) induced by 3-methylcholanthrene.     

Hemolytically active components from P. parvum and G. breve toxins

Hemolytically active fractions were isolated from the toxins produced by the red-tide dinoflagellate $\text{Gymnodinium breve}$ (GBTX) and the chrysomonad $\text{Prymnesium parvum}$ (PPTX). High pressure liquid chromatography through bonded phase (ODS) silica columns using a gradient of methanol in chloroform yielded 6 major fractions from GBTX, 3 of which were hemolytic (HD₅₀=0.3?0.56 μg·ml^?1). None were ichthyotoxic. Of the 6 fractions obtained from PPTX, 4 were hemolytic (HD₅₀=0.013?2.8 μg·ml^?1) but only one (fraction 6) was ichthyotoxic. This fraction was ～ 2000 times more hemolytic than the crude PPTX (HD₅₀=33.2 μg·ml^?1). Analysis of their UV spectra indicates that the fractions within each group are closely related.     

D-LSD binding to brain homogenates: possible relationship to serotonin receptors

Using a rapid filtration technique we find stereospecific high-affinity $\text{d}$-LSD binding (4 × 10^?9M, half-saturation) in brain fractions from a number of subcortical as well as cortical brain regions. Among the putative neurotransmitters tested only serotonin effectively displaces $\text{d}$-LSD from this specific binding site. Moreover, only the serotonin-displaceable component of binding is saturable in a high-affinity range. No change is observed in specific $\text{d}$-LSD binding in forebrain homogenates from rats in which ascending serotonergic pathways are destroyed by lesions in the raphe nucleus. We conclude that a vast majority of the $\text{d}$-LSD binding sites may be associated with a postsynaptic serotonin receptor rather than a presynaptic receptor associated with serotonergic (raphe) inputs.